Standard Operating Procedures for Managing STIR/SHAKEN Attestation Levels in Outbound Dialing

Outbound call centers and enterprise dialing operations today must navigate the STIR/SHAKEN caller ID authentication framework to ensure their calls reach customers. A critical part of this framework is the attestation level assigned to each call – A, B, or C – which signals how much the originating carrier trusts the call’s source. 

This comprehensive guide outlines SOPs and best practices for managing attestation levels A, B, and C from an operational perspective. We’ll explain what each attestation means, how it affects call deliverability and spam tagging risks, and how to implement procedures to maximize your call completion and reputation. 

We’ll also cover verification steps for A-level attestation, ways to improve your call reputation (including registering numbers with analytics services), ongoing monitoring and remediation, and tips for communicating these policies across your teams.

By following these best practices, call center professionals and outbound dialing operations can increase answer rates, reduce “spam likely” labels, and maintain compliance with industry standards. Let’s dive in.

Attestation Levels A, B, and C – What They Mean and Why They Matter

In the STIR/SHAKEN framework, every outbound call gets tagged with an attestation level A, B, or C. This attestation is essentially a measure of the originating provider’s confidence in the caller’s identity and right to use the phone number. Here’s a brief overview of each level:

• Full Attestation (Level A): The highest level of trust. Attestation “A” means the originating carrier has fully authenticated the calling party’s identity and confirmed they are authorized to use the outbound Caller ID number. In practical terms, the carrier knows its customer (Know Your Customer, or KYC) and has verified that the phone number used for the call belongs to that customer or is under their control. This is the gold standard.

• Partial Attestation (Level B): A middle level of trust. “B” attestation means the carrier has authenticated the customer’s identity (they know who is making the call) but has not verified the caller’s authority to use the number presented. In other words, the call is from a known customer, but the number might not be one the carrier issued to that customer (no formal proof of number ownership on file).

• Gateway Attestation (Level C): The lowest level of trust. “C” attestation (often called Gateway attestation) is used when the originating provider cannot verify the call source at all – typically because the call came in from an external network or gateway with no caller identification info beyond the incoming trunk. The carrier basically says, “this call came through my switch but I don’t know the caller.” This is common with traffic from international partners or other unknown sources.

Why do these levels matter? The attestation level serves as a trust indicator to terminating carriers and analytics engines. It can heavily influence whether your calls get through and how they are labeled to the recipient:

• An A-level attestation is viewed as low risk, and calls signed with A are generally considered “verified” calls that can be trusted. Some mobile devices will even display a special indicator (like a checkmark or “Caller Verified” text) for calls that arrive with full attestation, giving the consumer confidence that the call is legitimate. This can directly improve answer rates, since people are more likely to pick up calls that are verified and not marked as spam.

• A B-level attestation still indicates the caller is known to the provider, but the lack of number verification means there’s a bit less trust. These calls do not get the “verified” checkmark on phones (no STIR/SHAKEN trust indicator shows up). While B-level calls are STIR/SHAKEN compliant and will pass the authentication checks, they don’t carry the same weight of assurance as A-level. They might be delivered normally, but if other factors (like calling patterns or consumer feedback) are borderline, the lower attestation could contribute to a call being flagged by analytics.

• A C-level attestation is essentially a red flag. It tells the terminating carrier that the call’s origin is unverified or coming from an indeterminate source. Such calls are at high risk of being blocked or labeled as spam by default. In fact, some major carriers have policies to outright block calls with C attestation because they can’t be confidently traced. Even if not blocked, they are extremely likely to show up as “Spam Likely,” “Scam Risk,” or similar on the recipient’s phone. One industry expert bluntly put it: C-attested calls are effectively “dead on arrival” – the call will probably never reach a live person in a useful way.

It’s important to note that attestation is not the only factor in call blocking or labeling algorithms – but it is a significant one. Think of attestation as your baseline trust score:

If you can achieve Attestation A on your calls, you give yourself a strong foundation. Starting with that high trust level “adds another layer of trust” to your calls and makes it less likely (though not impossible) that they’ll be auto-blocked or diverted. You also qualify for those “Caller Verified” indicators which can improve answer rates by assuring recipients the call is legitimate.

Anything less than A puts your calls at risk. As TransUnion (a provider of call branding solutions) explains, calls that are attested at B or C are more likely to be marked as spam or even blocked by the receiving carrier. Carriers treat lower-attestation calls with more suspicion; it’s an input to their spam-detection algorithms. Your goal should be to avoid B and C except where absolutely necessary.

No attestation (unsigned calls) – while increasingly rare in an all-IP network – would be treated as high risk as well. In the U.S., virtually all legitimate carriers now sign calls with at least A or B if the call originates on their network. If a call isn’t signed, that’s a major red flag to terminating carriers that the call could be spoofed or from a non-compliant source. (If your calls are not signed at all, it likely means your carrier or path is not STIR/SHAKEN compliant – which is a serious issue to address in itself.)

That said, attestation alone is not a magic bullet. As some in the industry have observed, having A-level attestation does not guarantee your call won’t be labeled spam if your calling behavior is problematic. 

A fully authenticated telemarketer can still be flagged if, for example, they make thousands of short-duration calls that annoy recipients. The STIR/SHAKEN system is about verifying identity, not assessing call purpose or content – so it must work hand-in-hand with good dialing practices and reputation management. 

In the following sections, we’ll focus on how your organization can operationally achieve and maintain the highest attestation levels possible (ideally A for most calls) and implement best practices to keep your call reputation positive.

Criteria and Steps for Assigning Attestation Levels in Your Organization

Managing attestation levels on outbound calls requires establishing clear criteria for when a call (or calling campaign) can be given Full (A) attestation versus Partial (B), or when only Gateway (C) attestation is available. As an operational practice, your goal should be to assign the highest appropriate attestation level for every call, and avoid C attestation altogether. Here are the recommended steps and criteria to use:

1. Know Your Caller (KYC Verification): Treat the process of enabling a new outbound caller (whether it’s an internal department, a client of your call center, or a new campaign) similarly to a customer onboarding. Verify the identity of the calling party. This means collecting information on the business or entity making the calls, confirming their legitimacy, and ensuring you have a record of who they are. Only proceed if this KYC check passes. Attestation A and B both require that the service provider “knows the customer” initiating the call. If you don’t know (or can’t determine) who is actually making the call, you’re essentially dealing with anonymous traffic – which should default to C attestation (or be rejected entirely). Bottom line: never assign A or B to a caller you haven’t vetted.

2. Validate Telephone Number Ownership/Authorization: For every outgoing Caller ID number that will be used, establish whether the caller is authorized to use it. This is the key distinction between A vs. B attestation. You should have a procedure to verify the right-to-use of the phone number:

   • If the number is one assigned by your own system or carrier to that caller (for example, a DID you gave to the client, or a number you host for them), you inherently have that association on record – great, this satisfies the number verification for A attestation.

   • If the number is brought by the caller from another provider (a common scenario in call centers that dial on behalf of clients using the client’s business numbers), you need proof that the caller legitimately controls that number. The standard approach is to obtain a signed Letter of Authorization (LOA) or similar documentation from the number’s owner, explicitly authorizing you (or your carrier) to use and sign calls on that number. Keep this LOA on file. Some providers might use database dips or APIs to validate number ownership as well, but an LOA is a straightforward legal document for this purpose.

   • In cases where direct documentation isn’t available, consider using an approved third-party vetting service to validate the number’s association with the caller. These services (referred to by the FCC as “third-party vetting services”) can independently confirm that a given business or customer is the rightful user of a telephone number. For example, large enterprises that have numbers from multiple carriers might undergo a vetting process so that any originating carrier can trust the association and assign A-level attestation.

3. Assign Attestation Based on Verification Results:

   • If both the caller’s identity (Step 1) and the number’s ownership (Step 2) are verified, you can confidently assign Full Attestation (A) to that call. Essentially, you as the provider would be saying “This is my customer, and this is their number”. This is the ideal scenario for all your outbound traffic.

   • If the caller’s identity is verified (known customer) but you cannot verify the number’s ownership, then use Partial Attestation (B). In this case you’re saying “This is my customer, but I can’t vouch for the number they’re using”. Operationally, you should strive to minimize B-attested calls by finding ways to validate numbers (e.g. requiring that LOA!). But B is acceptable when number vetting falls short – it still indicates a known caller. Important: If a client refuses to provide proof of number ownership or uses numbers that can’t be traced, that might be a red flag in itself. You may decide not to allow that traffic, or only send it with B attestation and heightened monitoring.

   • If neither the number nor the caller can be verified (or the call is coming from outside your network control), then it falls to Gateway Attestation (C). This should be rare in an outbound call center scenario, because presumably you know your own clients or call originators. C attestation is typically seen when you’re simply transiting traffic from elsewhere. From an SOP perspective, you should avoid handling or originating calls that would only qualify for C attestation. As noted earlier, C-level calls are extremely likely to be blocked or tagged as spam, and even carriers warn that C attestation is effectively the death of a call. If you find that some of your calls are ending up with C, investigate why – it could be due to a technical routing issue (e.g. calls unintentionally going out through a gateway that strips info) or a process gap in your verification steps. Ideally, do not originate calls with C attestation at all as a matter of policy. If a call can only get C, you might choose not to place that call until you have more information.

4. Document the Attestation Decision Criteria: As part of your SOP, create a checklist or form that is filled out for each new campaign or caller onboarded into your dialing system. This checklist should cover:

   • Customer identity verified (Yes/No – if no, stop here).

   • Numbers to be used listed and ownership verified (list evidence such as “Number purchased from our carrier” or “LOA on file dated X”). For each number, mark if it’s verified for A.

   • Designated attestation level for that client or campaign’s calls. (In many cases it will simply be “All calls attested A” if all numbers are verified. In some cases it might be “attest B for calls from number X, Y which we couldn’t verify ownership”). This documentation will help in internal audits and if questions ever arise about why a certain call was signed a certain way.

5. Implement Controls in Your Dialing Platform: Ensure that your dialing/telephony platform has the capability to assign or pass the correct attestation. If you are using a SIP trunk or CPaaS provider, coordinate with them on how they determine attestation for your calls. Many providers will automatically give A attestation if your account is using numbers you acquired through them or have verified, and will downgrade to B if not. For example, some cloud dialer services note that when you use your own number, they first verify you control it to obtain B-level attestation; whereas numbers you buy from them get A-level. Work with your carrier to ensure they have your verified numbers documented so that your calls actually receive the A attestation you expect. This might involve uploading LOAs or lists of numbers to their portal.

6. Revisit and Update Attestation Assignments as Needed: The attestation level is not necessarily static forever. If a client initially had B (because, say, their number wasn’t verified) and later they provide proof or you port the number to your service, update their status to A. Conversely, if a customer starts behaving suspiciously or you lose confidence, you might downgrade future calls to B or even stop service (more on monitoring later). Have a process to periodically review which clients/campaigns are at B and see if you can elevate them to A by fulfilling any missing requirements (this improves everyone’s outcomes).

SOPs for Verifying Call Originator Legitimacy and Caller ID Integrity (Qualifying for A-Level Attestation)

Achieving A-level attestation consistently requires robust front-end procedures to verify the legitimacy of callers and the integrity of their caller IDs. Here we outline standard operating procedures to ensure any call you originate merits full attestation. These SOPs should be ingrained in your compliance and operations process:

• Strict KYC (Know Your Customer) Process: Before allowing any entity to send outbound calls through your system, perform a KYC check. This involves verifying the organization’s identity (e.g., business name, address, relevant licenses or registrations), understanding their line of business, and making a reasonable assessment that they are a legitimate caller (not a scam operation). The FCC’s robocall mitigation best practices stress collecting sufficient subscriber identity information as a prerequisite to confidently attesting calls. Have the customer fill out an onboarding form that captures key details, and verify those details (via business registration databases, web research, etc.). If something doesn’t add up (e.g., a business claims to be a well-known brand but you can’t verify that relationship), do not proceed with signing their calls as A. Only trusted, vetted customers/partners should be allowed on your outbound platform.

• Caller ID Number Verification and Authorization: For each phone number that will be used as Caller ID:

  • Determine the source of that number (did it come from your inventory or an external source?).

  • If it’s from your inventory or provided by your carrier to the customer, you have an inherent authorization trail. Just ensure it’s assigned to the right customer in your records.

  • If it’s from an external source, obtain a Letter of Authorization (LOA) or equivalent written permission indicating the number’s true owner allows its use. The LOA should ideally be specific about allowing your company (or your carrier) to use and sign that number. Maintaining a file of LOAs is now a common industry practice to enable full attestation for bring-your-own numbers. For example, a call center dialing on behalf of “Acme Corp” might have Acme’s telecom provider or legal representative sign an LOA stating that number (say 212-555-1234) is owned by Acme and Acme consents to its use in the call campaign through your service.

  • As an additional step, you might cross-verify the number’s ownership. Some methods include querying the national number portability database or carrier APIs to see which carrier currently holds that number and in whose name. If you find a mismatch (e.g., client claims a number that the databases show belongs to someone else entirely), that’s a red flag to resolve before granting A-level attestation.

  • Record-Keeping: Log when and how each number was verified. Keep copies of LOAs and notes of any database checks. This documentation not only helps maintain integrity but could protect you if there’s ever a challenge or traceback inquiry about a number you attested (you can show you did due diligence).

• Enforce Caller ID Integrity in Dialing Systems: Technically configure your dialers and SIP trunks such that only approved caller ID numbers can be used by each campaign or client. Many systems allow you to assign specific caller IDs to campaigns – use this to prevent agents or software from arbitrarily inserting numbers that haven’t been vetted. Essentially, lock down the caller ID field. This ensures that even by mistake no one is using an unverified number. Some organizations maintain a whitelist of outbound numbers for each client; if a number isn’t on the whitelist, the system won’t let it be used. This guarantees that if you’ve verified five numbers for Client A, the callers can only use those five, nothing else.

• Continuous Caller ID Auditing: Periodically audit the caller IDs in use vs. your verified list. Remove any numbers that are no longer authorized or in use. For instance, if a client’s campaign ended and they no longer use a number, make sure it’s not left in the system to be accidentally reused elsewhere without fresh vetting (numbers can age and be reassigned, etc.). If a number gets ported away to another carrier, you should probably stop using it unless you have updated proof of authorization. Regular audits (say, monthly or quarterly) will catch any stragglers or mistakes.

• Leverage Trusted Calling Programs: Some carriers and industry initiatives offer programs to streamline this verification. For example, there are “Trusted Caller” or enterprise attestation programs where an enterprise can pre-register their numbers and identity with a centralized authority. If you participate in such programs (often run by major carriers or the SHAKEN governance authority), make sure those registrations are up to date. This can help in getting A-level attestation across the board. As an example, some voice providers require businesses to complete a “Trusted Call Completion” application – providing all their company and number details – as part of enabling SHAKEN on their calls. Make such processes part of your onboarding SOP.

• Training and Accountability: Ensure that those in charge of onboarding new clients or campaigns (whether it’s a compliance manager or operations lead) understand these verification steps and why they are crucial. They should treat verifying a number and identity as a mandatory checkpoint, not a nice-to-have. Make it an accountable item in your project management – e.g., a campaign cannot go live until the compliance team signs off that “All caller IDs verified, OK for full attestation.”

By rigorously verifying caller legitimacy and number authorization upfront, you qualify your calls for A-level attestation. This upfront work pays off in higher call completion and fewer headaches later. It essentially “earns” you the right to have your calls pass through telecom networks with a seal of authenticity, which, as we’ve discussed, is increasingly essential for reaching customers in the robocall-blocking era.

Best Practices to Improve Call Reputation and Reduce Spam Labeling

Beyond just assigning attestation, there is a broader set of best practices your operation should follow to maintain a good caller reputation. Even with A-level attestation, poor dialing practices can still result in spam labels. Here are key practices (including registration with analytics services) to keep your calls trusted and answered:

• Register Your Numbers with Analytics/Labeling Services: A critical step in today’s environment is to proactively register all your outbound numbers with the major call analytics engines that carriers use for spam detection. In the U.S., the three main analytics providers are First Orion, Hiya, and TNS (Transaction Network Services). They power the “Spam Likely” or call labeling systems for most wireless carriers. These companies have a streamlined Free Caller Registry portal where you can submit your organization’s information and phone numbers. By registering, you inform these analytics services about your business and the nature of your calls. This can support the reputation of your phone numbers and help ensure they are recognized as legitimate. It’s not a guarantee that you’ll never be labeled (more on that in a moment), but it significantly helps. Essentially, registration provides the algorithms with context – it’s like saying “We’re Company X, these numbers belong to us, and we’re calling for XYZ reason.” According to industry experts, this often improves your initial reputation score and mitigates risk of erroneous spam tagging. Make it an SOP to register any new number before it starts making large volumes of calls. Tip: Revisit your registrations periodically to add or remove numbers as campaigns change.

• Understand That Registration != Immunity: While registering numbers is important, don’t get complacent after doing it. Even numbers on these registries can still be flagged if their behavior resembles spam or if complaints roll in. Think of registration as a preventive measure and reputation booster, not an absolute shield. The analytics companies themselves note that they do not offer permanent “whitelisting” for anyone – they always monitor call behavior. So use registration in tandem with the other best practices below.

• Maintain Consistent Caller ID Name (CNAM) Data: Ensure that for each phone number, the Caller Name (CNAM) record (if applicable) is set to reflect your organization or your client’s name accurately. While CNAM databases are separate from STIR/SHAKEN, they still play a role in how calls appear and can influence recipients’ trust. If a carrier dips CNAM and finds no name or a mismatched name (e.g., your agent says “Hi this is Acme Corp” but the CNAM says “John’s Pharmacy” due to a reused number), it creates confusion and might lead to negative feedback. It’s best practice to have the CNAM aligned with the brand or campaign. Also consider emerging branded calling solutions – for example, some services allow you to display your company’s name or logo on the recipient’s screen (on supported devices/networks) through an enhanced caller ID service. These often require having your numbers and business registered as well. If your volume and use-case justify it, branded calling can significantly increase answer rates by giving a clear, trusted identity display. At minimum, make sure each number’s CNAM is up-to-date and consistent with how you identify yourselves on the call.

• Use a Stable Pool of Numbers (Don’t Rapidly Rotate or Spoof): In the past, some telemarketers tried to evade spam labeling by constantly changing or rotating their caller ID numbers (or spoofing random numbers). Today, those tactics are strongly discouraged and often counterproductive. Carriers and analytics have become wise to number rotation patterns. In fact, frequently switching numbers or using a large pool of numbers for the same campaign can itself raise red flags. Best practices suggest using a consistent set of numbers and building a positive history with them. When you acquire new numbers, “age” them appropriately – some recommend letting a number rest if it was used previously, and not immediately blasting thousands of calls from a fresh number. If you do use multiple numbers, assign each a consistent purpose (don’t mix different campaign traffic on the same number if possible, which could confuse labeling algorithms about the number’s intent). The key is to have a predictable dialing pattern for each number. Sudden spikes or irregular bursts are what algorithms catch. For example, instead of each number making 1000 calls one day and zero the next, try to spread calls evenly or limit spikes. Carriers monitor the “standard deviation” of call patterns per number. A number that goes from 0 to 500 calls in a day out of the blue might trigger scrutiny. Plan your campaigns to ramp up gradually on new numbers and maintain steady volumes.

• Avoid “Spray-and-Pray” Dialing Tactics: High-volume, short-duration call campaigns (e.g., dialing tens of thousands of numbers with a few seconds of ring time or a quick hang-up) are a recipe for being labeled spam. Modern analytics look at call answer rates, call durations, and user behavior after answering. If very few people are picking up your calls, and those who do answer hang up quickly (or you hang up quickly), it signals the calls might be unwanted or robocalls. Strive to improve answer rates by calling target lists that are more likely to pick up (for instance, customers who are expecting your call or who have opted in). And when someone does answer, ensure your agents or system engage for at least a minimal conversation. A commonly cited metric: if a significant percentage of your answered calls last over 30 seconds, it actually boosts your reputation with carriers. It indicates the call recipient didn’t immediately hang up in annoyance – implying the call was more legitimate or welcome. On the flip side, a pattern of many calls under 10 seconds (especially if the caller hung up) strongly suggests robocall behavior (like autodialers that hang up if no agent is free, etc.). So:

  • Tune your dialer to avoid excessive abandoned calls.

  • If using answer machine detection, be careful it’s not hanging up on real people by mistake.

  • Consider leaving voicemails rather than just disconnecting on no-answer – a voicemail can at least signal you’re a real business and not a random scam robocall.

  • Monitor your contact rate (pickups vs dials) and average call duration as key health indicators.

• Ensure Legal and Regulatory Compliance: Following telemarketing laws not only avoids fines, it protects your number reputation. Carriers do pay attention to complaints and official reports. If your number accumulates complaints in the FCC or FTC databases, it’s likely to get tagged. Always scrub against the National Do Not Call (DNC) list and any internal DNC lists. Obtain proper consent for any auto-dialed or pre-recorded calls as required by the TCPA and other regulations. Not only is it legally required, but if you call consumers without consent, you greatly increase the chance they will report your call as spam or scam, damaging your reputation. Train agents to adhere to opt-out requests and be polite – a single rude interaction can lead to a complaint that sticks to your number’s record. Many carriers and analytics companies ingest consumer complaints (from carrier feedback mechanisms or regulatory sources) and weigh them heavily. So a good compliance program is actually a good reputation strategy too.

• Time Your Calls Considerately: This is more of a soft best practice, but calling during appropriate hours and not over-calling the same number repeatedly will reduce the chance of recipients labeling you as spam. If one of your numbers repeatedly calls the same person 5 times in an hour, there’s a good chance that person will hit the “report spam” button on their cellphone. Spread out retry attempts and respect cooldown periods.

• Monitor Consumer Feedback Loops: Some carriers provide feedback if users explicitly block or label your number. For example, analytics services may have dashboards showing how many times your number was tagged or what its current reputation score is. Make use of these if available. It’s better to catch early if one particular number is starting to trend negatively (maybe because one agent used it in a less-than-stellar way).

• Use Call Branding (When Available): As mentioned, branded calling services (like Verified/Branded Calls, SHAKEN-rich call data frameworks, etc.) can present your brand identity directly on the incoming call screen for certain carriers or smartphone apps. If your operation has the resources, enrolling in these services can differentiate your calls from generic spam. For example, some solutions working with STIR/SHAKEN allow an enterprise to attach a rich call data token that displays your business name, logo, and reason for calling on the recipient’s device. These typically require coordination with carriers and are an extension of STIR/SHAKEN framework. This is an emerging area, but keep an eye on it as it could become a best practice for legitimate outbound dialing to distinguish themselves from spammers.

In summary, think of building call reputation like building a sender reputation in email marketing – use consistent “from” information, send wanted communications, avoid spammy patterns, and monitor your sender score.

Attestation gives you a leg up (especially A-level attestation), but the content and behavior of your calls must reinforce that trust. Many legitimate call centers have seen improved answer rates by implementing these practices, such as registering their numbers and adopting more measured dialing tactics, thereby escaping the “spam likely” trap.

Ongoing Monitoring, Auditing, and Remediation Procedures

Even with solid upfront practices, ongoing monitoring and quick remediation are essential parts of managing attestation and call reputation. You should have SOPs in place to continuously watch what’s happening with your outbound calls and to react to any issues (like a number getting flagged) before they escalate. Here’s how to structure that:

• Monitor Attestation Levels on an Ongoing Basis: It’s a good idea to regularly check that your calls are indeed going out with the intended attestation. Many providers will include the attestation info in SIP headers or call detail records. If you have access to that, spot-check that calls expected to be “A” are actually being tagged as “A” by your carrier. You can also do simple tests: make test calls to a variety of destinations (including perhaps your own phone). Some phones or carrier voicemail systems will indicate if a call was verified (A) or not. For example, certain wireless carriers show a ✅ checkmark on the phone display or in the recent calls list for verified calls. If you find your calls aren’t showing as verified when they should be, investigate with your carrier – there could be a technical issue or a misconfiguration on your account that’s causing a downgrade to B. Catching that early ensures you fix any attestation leakage.

• Monitor Call Labeling and Reputation:

  
  

  • Self-test your numbers by calling devices on major carriers (AT&T, Verizon, T-Mobile, etc.) to see if any “Spam Likely” or similar warning appears. Ideally, set up a routine (e.g., weekly) where someone in your team dials each active caller ID from a test phone on each major network and notes the display. It’s a manual approach but can catch problems.

  • Use third-party monitoring tools: There are services and products designed to monitor phone number reputation. These services will periodically test your numbers across many networks and report if any come back with a spam label or are blocked. For example, companies like Numeracle, CallerIDReputation, or Number Sentry offer tools to automate this. They often will continuously monitor your registered numbers and alert you to any instances of them being labeled as spam or fraud. Such tools can save a lot of time and catch issues early. If your operation is large (many numbers, high call volume), investing in a reputation monitoring service is wise.

  • Track answer rates and connect metrics: A sudden drop in answer rate or a spike in customers saying “we never got your call” can indicate your calls are being blocked or labeled. Your QA or analytics team should keep an eye on connect rates by campaign and number. Any anomaly should prompt a closer look (e.g., maybe that number got flagged).

• Conduct Regular Attestation Audits: Every so often, perform an internal audit of your attestation assignment process:

  
  

  • Review the list of all outbound numbers and verify you have current LOAs or proof for each.

  • Review which clients/campaigns are on B attestation and see if circumstances have changed to upgrade them to A (or if they should be pushed to do so).

  • Ensure no new outbound traffic sources have been added without going through approval. This is to prevent a scenario where, for example, an IT person connected a new SIP trunk or a new call gateway that isn’t configured for STIR/SHAKEN – resulting in unsigned or C-level calls. An audit might catch “hey, why are some calls from this new IP showing attestation C?” and then you can address it.

  • Check compliance with the processes: are the forms being filled, LOAs collected, etc.? If any step was skipped, correct it.

  
  

• Remediation Plan for Spam Labeling or Blocking:

  
  

  • Despite best efforts, you may encounter a situation where one of your numbers gets labeled as “Spam Risk” or outright blocked by a carrier. It’s critical to have a documented remediation procedure to respond swiftly. Time is of the essence because the longer you continue dialing with a flagged number, the deeper the damage (more negative answers or lack of contact).

  • Step 1: Pause and investigate. If you confirm or strongly suspect a number is being flagged (e.g., your monitoring shows it, or customers tell you “your call came up as spam”), pause using that number immediately. Continuing to call from it will just rack up more negative reputation. While paused, investigate what might have caused it. Was there a surge in calls? A particular call campaign that drew ire (lots of hang-ups or complaints)? Or was the number new and got misidentified?

  • Step 2: Initiate correction with analytics providers. Since you’ve registered your numbers (per best practices), you often have a line of communication to the analytics teams. The Free Caller Registry and individual analytics companies provide channels to request remediation if you believe your number was incorrectly labeled. Submit a ticket or report stating your number, who you are, and that your calls are legitimate and should not be flagged. Provide any supporting info (e.g., “we are calling customers who opted in for reminders, etc.”). The analytics companies will review and, if all checks out, can remove the spam tag for the number. This process can take some time, so it’s another reason to pause calling until resolved.

  • Step 3: Adjust your practices. While you work to get the label cleared, also address any internal cause. For example, if the number was flagged because call volume jumped 5x last week, then smooth out your dialing rates or split traffic over additional verified numbers. If it was due to calling sans consent, immediately correct that practice. Essentially, fix whatever triggered the algorithms so it doesn’t happen again.

  • Step 4: Use an alternate number if necessary. If you have a critical campaign that can’t wait, you might deploy a different (clean) number temporarily. But do this carefully: the alternate number should also be one that’s verified and registered, and you should perhaps throttle the call volume lower for a while to “fly under the radar” while you sort things out. Also, be aware that if your underlying practices don’t change, the new number could quickly get tagged too. So this is more of a last resort to keep operations running when absolutely needed.

  • Step 5: Verify the fix and resume. After you believe the issue is resolved (e.g., you’ve been notified by the analytics service that the label was removed, or your test calls no longer show spam), you can resume calling from that number. Monitor it very closely for a while after – if the label reappears, you might need more drastic changes.

  • Document these incidents in an internal log. Note which number was affected, when, what the cause likely was, and how it was resolved. This can help prevent future occurrences and is useful information to share with your team (learning opportunity).

    
    

• Robocall Mitigation and Traffic Monitoring: If you are a carrier or responsible for large-scale traffic, the FCC and industry expect you to have ongoing robocall mitigation programs【24†】. Even if you’re not a carrier per se, from an operational standpoint act as if you are responsible for policing your own calls.

  
  

  Implement analytics on your outbound traffic to spot patterns consistent with illegal robocalls (e.g., high-volume short-duration bursts, calls that result in a high percentage of unanswered or blocked events, etc.). Should you find any anomaly – say one agent or sub-client generating a disproportionate share of negative outcomes – investigate and take action.

  
  

  This might involve retraining an agent, throttling a campaign, or in extreme cases, dropping a problematic client. By actively mitigating potentially harmful traffic, you protect your entire calling ecosystem and maintain the privilege of A-level signing. Remember, carriers are under pressure to not carry spam; if your operation is seen as a source of spam, you risk more than just number labeling – you could be blocked at a network level or lose service contracts. So treat mitigation seriously.

  
  

• Leverage Real-time Monitoring Tools: Some providers (like QVD in our earlier example) offer real-time monitoring and remediation services that integrate with your dialing – these can automatically alert or even take action if calls are being improperly blocked or labeled. If your provider offers such a feature, take advantage of it. It might notify you instantly if a call gets a certain treatment, allowing you to react in real time.

In summary, monitoring and remediation is about staying vigilant and being ready to fix issues quickly. Your SOP should make someone (or a team) explicitly responsible for this oversight. It’s not “set and forget.” Have weekly if not daily checks on key metrics. Treat your phone numbers like assets whose reputation you must guard.

As one expert blog noted, number registration is just the first step – the real work is the continuous monitoring and advocacy to keep your numbers clean. Outbound call operations that dedicate resources to this ongoing process tend to have far more success in reaching customers consistently than those who assume everything is fine until it’s not.

From “Verified” to Answered—Put These SOPs on Autopilot with Tendril

Managing STIR/SHAKEN on paper is one thing; enforcing it across dozens of campaigns, trunks, and caller‑ID pools is another. Tendril Connect bakes the entire playbook into your outbound stack:

• A‑Level Attestation, Every Time – Built‑in KYC workflows, number‑ownership LOA vault, and automatic STIR/SHAKEN signing ensure your calls leave the switch with a gold‑seal “A.”

• Real‑Time Reputation Guardrails – Continuous API checks with First Orion, Hiya, and TNS flag issues before carriers do. If a number trends toward “Spam Risk,” we auto‑pause and route through a clean line while remediation tickets fire.

• One‑Click Number Registration & Branding – Submit new DIDs to Free Caller Registry, lock CNAM, and activate branded‑call logos—all inside one dashboard.

• Adaptive Dial‑Pacing – AI throttles or ramps volume based on live answer‑rate signals so you never trigger analytics thresholds that downgrade attestation.

• Audit‑Ready Logs – Every LOA, attestation decision, and remediation step is timestamped for quick tracebacks or FCC audits.

Focus on converting prospects—not chasing spam labels. Book a quick demo to see how Tendril turns your SOPs into set‑and‑forget guardrails that keep every ring verified, delivered, and answered.