Stir Shaken’s Impact on Call Center Operations

STIR/SHAKEN has changed how call centers manage outbound caller identity, phone numbers, carrier relationships, call analytics, and dialing operations. The framework helps telecommunications providers verify whether the caller ID associated with an internet-based call is authorized for use by the originating provider or customer.

For legitimate outbound teams, STIR/SHAKEN is an important part of the call-connectivity process—but it is not a guarantee that every call will be answered, completed, or protected from a Spam Likely label. Carriers and call-analytics providers may also evaluate call volume, answer patterns, complaints, call duration, number history, and other reputation signals.

This guide explains STIR/SHAKEN’s impact on call center operations and the practical steps teams can take to improve caller identity, protect number reputation, and build a more sustainable outbound calling process.

What Is STIR/SHAKEN?

STIR/SHAKEN is a set of technical standards used to authenticate caller ID information on calls that travel through internet-based telephone networks.

The name combines two related standards:

• STIR stands for Secure Telephone Identity Revisited.
• SHAKEN stands for Signature-based Handling of Asserted Information Using toKENs.

When an eligible call originates, the originating voice service provider can attach a digital certificate containing information about the caller ID and the provider’s level of confidence in the calling party’s authorization to use that number. Providers handling the call can validate the certificate as the call travels toward the recipient.

The primary purpose is to make illegal caller ID spoofing more difficult and give providers additional information about a call’s origin. Learn more in What Is STIR/SHAKEN?

How STIR/SHAKEN Call Authentication Works

A simplified STIR/SHAKEN call flow generally includes the following stages:

1. The call originates. A business or call center places a call using an outbound phone number.
2. The originating provider evaluates the call. The provider determines what it knows about the calling party and whether that party is authorized to use the displayed caller ID.
3. An identity token is created. The provider digitally signs call information and applies the appropriate attestation level.
4. The call enters the telephone network. The identity information travels with the call when supported by the participating networks.
5. The terminating provider validates the signature. The recipient’s provider checks whether the token is valid and whether the caller ID information has been altered.
6. Other analytics may also be applied. Authentication becomes one signal among several that may influence call treatment, labeling, or display.

STIR/SHAKEN validates information about the call’s origin and caller ID authorization. It does not prove that the caller’s message is truthful, that the recipient wants the call, or that the call complies with every applicable law.

Understanding STIR/SHAKEN Attestation Levels

STIR/SHAKEN commonly uses three attestation levels. These levels describe what the originating provider knows about the customer and their authorization to use the displayed number.

A-level attestation is generally preferable, but it still does not guarantee call completion, a verified display, or protection from spam labeling. Attestation is only one part of the broader call-reputation environment.

How STIR/SHAKEN Affects Call Center Operations

1. Greater Attention to Caller ID Authentication

Call centers can no longer treat the outbound caller ID as a simple display setting. Teams must understand where their numbers come from, which provider originates their calls, and whether the provider can authenticate those numbers appropriately.

This requires closer coordination among the call center, dialer platform, voice service provider, number provider, and any other vendors involved in originating or routing the calls.

2. More Structured Number Provisioning

Outbound numbers should be properly assigned to the business and connected to accurate account information. Call centers may need documentation showing that they own, lease, or are otherwise authorized to use each number.

Using caller IDs that are not correctly associated with the originating account can affect the provider’s ability to apply the strongest appropriate attestation.

3. Increased Need for Business and Number Registration

STIR/SHAKEN authentication and phone number registration are related parts of the call-trust ecosystem, but they are not the same process.

STIR/SHAKEN helps providers authenticate the caller ID used on a call. Number registration allows a legitimate business to submit identity and calling information to participating carrier or analytics databases. Call centers may need both practices as part of a wider reputation strategy.

4. Changes to Dialing and Number-Management Workflows

Call centers must pay closer attention to the volume and behavior associated with each outbound number. A newly activated number that immediately generates unusually high call volume may still develop reputation problems even when its caller ID is authenticated.

Teams may need to warm new numbers gradually, begin with more controlled dialing, rotate numbers responsibly, and review performance before increasing campaign volume.

5. More Detailed Call Analytics

Total dials are no longer enough to evaluate outbound performance. Managers should review connectivity and reputation metrics at the campaign and phone-number level.

Useful metrics include:

• Connection rate.
• Live-answer rate.
• Meaningful conversation rate.
• Average call duration.
• Voicemail rate.
• Invalid-number rate.
• Appointments and conversions.
• Performance by outbound number.
• Possible spam-label status.
• Complaints and opt-out requests.

Learn more about the connection between authentication and reporting in How STIR/SHAKEN Influences Call Analytics and Reporting.

6. New Training Requirements for Representatives and Managers

Call center staff do not need to become telecommunications engineers, but they should understand how their behavior can affect number reputation.

Training should cover:

• Why accurate caller ID information matters.
• How repeated calls can affect the customer experience.
• When and how to leave a useful voicemail.
• How to record accurate call dispositions.
• How to process do-not-contact requests.
• Why representatives should not substitute unapproved caller IDs.
• How call quality and representative behavior affect complaints.
• When to report a sudden decline in answer or connection rates.

7. Greater Compliance and Vendor Oversight

STIR/SHAKEN does not replace telemarketing, consent, privacy, recording, suppression-list, or calling-hour requirements. Call centers remain responsible for understanding the rules that apply to their locations, industries, audiences, and communication methods.

Businesses should also evaluate whether their providers support appropriate authentication, maintain accurate customer information, monitor abuse, and offer a process for investigating call-delivery or labeling problems.

8. More Focus on Consumer Trust

Authentication is one part of rebuilding trust in phone communication. A legitimate caller should also use consistent identification, explain the reason for the call, respect the recipient’s preferences, and avoid misleading or overly aggressive tactics.

A digitally signed caller ID cannot compensate for a poor customer experience or an inappropriate campaign.

Does STIR/SHAKEN Improve Call Connection Rates?

Proper authentication can support call trust and help networks identify legitimate caller ID information. However, STIR/SHAKEN alone does not guarantee that a call will be connected, displayed as verified, answered, or protected from spam labeling.

Call completion and pickup rates may also depend on:

• The history and reputation of the outbound number.
• Whether the number has been registered with relevant databases.
• The number of calls placed within a given period.
• Repeated attempts to the same recipients.
• Answer and call-duration patterns.
• Customer complaints and opt-out behavior.
• The accuracy and age of the contact list.
• Calling times and local relevance.
• How originating and terminating providers handle the call.
• Third-party analytics and labeling systems.

This is why a call center may have authenticated calls and still experience low pickup rates. For a more detailed explanation, see Is STIR/SHAKEN Affecting My Pickup Rates?

STIR/SHAKEN vs. Spam Likely Labels

STIR/SHAKEN authentication and Spam Likely labeling are often confused, but they perform different functions.

Call centers should therefore use a layered strategy that includes authentication, registration, responsible dialing, monitoring, and remediation.

Why Authenticated Calls Can Still Be Flagged

STIR/SHAKEN answers an important question: can the originating provider verify the caller and their authorization to use the caller ID? Spam analytics attempt to answer a different question: does the call appear likely to be unwanted or abusive?

An authenticated number can still be flagged when its activity produces negative reputation signals, such as:

• A sudden increase in outbound volume.
• Large numbers of short or unanswered calls.
• Repeated attempts to the same contacts.
• High complaint or block rates.
• Poor-quality or outdated lead data.
• Calling patterns that resemble automated abuse.
• A previously damaged number history.

Authentication should therefore be treated as a foundation—not a complete call-connectivity solution.

How to Prepare Outbound Numbers for Calling

New or recently assigned numbers should be prepared before being used for full campaign volume. A responsible launch process can help the team detect configuration or reputation issues early.

1. Confirm number ownership or authorization. Verify that every outbound number is properly assigned to the business account.
2. Keep business information consistent. Use accurate business names, addresses, contact details, and other requested information across provider and registration records.
3. Ask about authentication. Confirm how the originating provider handles STIR/SHAKEN and what information it requires to provide the appropriate attestation.
4. Register the numbers. Submit legitimate business and campaign information through the appropriate registration processes.
5. Test the initial configuration. Place controlled test calls and confirm that the intended caller ID appears correctly.
6. Warm up gradually. Begin with a manageable number of calls and increase activity progressively.
7. Monitor each number. Review connection rates, customer responses, and possible labeling issues.
8. Document changes. Keep a record of activation dates, registrations, campaigns, volume adjustments, and remediation attempts.

How to Warm Up New Phone Numbers

Number warm-up means starting a new outbound number with controlled activity instead of immediately pushing it to the maximum campaign volume.

A practical warm-up process may include:

• Starting with lower daily call volume.
• Using single-line dialing during the early stage when appropriate.
• Placing calls during normal local calling hours.
• Using accurate and permission-appropriate contact data.
• Allowing representatives to have natural-length conversations.
• Leaving useful voicemail messages when appropriate.
• Avoiding repeated attempts to the same prospect within a short period.
• Monitoring performance before increasing volume.
• Pausing or investigating when a number shows an unusual decline.

There is no universal warm-up schedule that guarantees a particular result. Appropriate volume depends on the business, campaign, provider, list quality, number history, representative capacity, and calling behavior.

Phone Number Rotation After STIR/SHAKEN

Phone number rotation can help distribute legitimate outbound activity across multiple numbers, but it must be used responsibly. Rotation should support organized number management—not conceal the identity of the caller or evade carrier safeguards.

A responsible rotation strategy may help teams:

• Match numbers to specific campaigns or markets.
• Avoid concentrating all activity on one number.
• Monitor performance at the individual number level.
• Temporarily remove a number that requires investigation.
• Maintain more consistent campaign capacity.

Simply replacing a flagged number without correcting the calling behavior that caused the problem may lead to the same outcome on the replacement number. Learn more in Rotate Your Phone Numbers With ProspectBoss and How Multiple Phone Numbers Support a STIR/SHAKEN Strategy.

Operational Changes Call Centers Should Consider

Create a Number Inventory

Maintain a central record of all outbound numbers, their providers, assigned campaigns, activation dates, registration status, and current performance.

Assign Clear Ownership

Designate a person or team responsible for number acquisition, registration, warm-up, monitoring, rotation, and remediation.

Use Accurate Call Dispositions

Representatives should consistently record answered calls, voicemail, requested callbacks, invalid numbers, not-interested outcomes, and do-not-contact requests. Reliable dispositions improve reporting and help prevent unnecessary repeat attempts.

Set Volume Controls

Establish reasonable daily and hourly activity levels based on representative availability, number history, campaign maturity, and performance.

Monitor by Number and Campaign

A strong overall connection rate can hide a problem affecting one number. Review performance at a sufficiently detailed level to identify sudden changes.

Create a Remediation Process

Define what the team should do when a number is mislabeled or experiences a sudden performance decline. The process may include verifying business information, reviewing recent dialing activity, checking complaints, submitting registration or remediation requests, and temporarily reducing volume.

Common STIR/SHAKEN Mistakes

• Assuming A-level attestation guarantees pickup. Authentication does not control the recipient’s decision or every carrier’s display.
• Confusing authentication with spam-label prevention. Carriers may still evaluate behavior and reputation signals.
• Launching new numbers at full volume. Sudden activity can create avoidable reputation risk.
• Using unverified caller IDs. The provider may not be able to confirm the business’s authorization to use them.
• Ignoring number-level analytics. Aggregated reports may hide individual number problems.
• Replacing numbers without correcting campaign behavior. The same pattern may damage each new number.
• Using a primary inbound line for heavy prospecting. Reputation issues could affect important customer callbacks.
• Failing to train representatives. Poor dispositions, repeated attempts, and mishandled opt-outs can damage results.
• Treating compliance as a one-time task. Provider requirements, call patterns, business information, and campaign needs can change.

How STIR/SHAKEN Changes Call Center Reporting

Call centers should evaluate more than productivity. A representative may generate a high number of dials while the campaign produces few meaningful conversations or damages outbound number reputation.

A balanced performance dashboard should include:

How ProspectBoss Supports Call Center Connectivity

ProspectBoss helps outbound teams manage CRM records, calling campaigns, dispositions, follow-up, reporting, and phone-number operations within one sales-focused workflow.

A stronger call-connectivity strategy may combine:

• Accurate and organized lead data.
• Appropriate dialing modes.
• Controlled number warm-up.
• Phone number registration.
• Responsible number rotation.
• Connection-rate monitoring.
• Accurate dispositions and suppression handling.
• Representative training and quality review.

ProspectBoss also offers Phone Registration and Spam Likely support to help teams manage number registration and address potential reputation issues.

No platform can guarantee that every call will receive a particular attestation, avoid every label, or be answered by the recipient. The goal is to reduce avoidable risks and create a healthier, more transparent outbound operation.

Frequently Asked Questions

What does STIR/SHAKEN do?

STIR/SHAKEN helps telecommunications providers authenticate information about a call’s origin and the caller’s authorization to use the displayed phone number. It is primarily designed to reduce illegal caller ID spoofing.

Does STIR/SHAKEN block calls?

STIR/SHAKEN itself provides authentication information. Voice providers and analytics systems may use this information with other signals when deciding how a call should be completed, labeled, displayed, or treated.

What is A-level attestation?

A-level or full attestation generally means the originating provider knows the customer and has verified that the customer is authorized to use the displayed caller ID.

Does A-level attestation prevent Spam Likely labels?

No. Full attestation can confirm caller ID authorization, but spam labeling may also consider volume, number history, complaints, answer patterns, call duration, and other reputation signals.

Can an authenticated call still be blocked or ignored?

Yes. Authentication does not guarantee call completion or pickup. The recipient may ignore the call, and carriers or devices may apply additional analytics and call-handling rules.

Why did pickup rates decline after STIR/SHAKEN?

A decline may be associated with authentication, but teams should also investigate number reputation, registration, calling volume, list accuracy, repeated attempts, calling times, carrier behavior, and spam labels.

Should call centers use multiple phone numbers?

Multiple numbers can help distribute legitimate activity and organize campaigns, but they should be properly registered, monitored, and rotated responsibly. They should not be used to hide caller identity or evade carrier protections.

How should a call center warm up a new number?

Start with controlled call volume, use natural calling behavior, avoid excessive repeat attempts, monitor the number’s performance, and increase activity gradually. There is no universal schedule that guarantees a specific result.

Is STIR/SHAKEN the same as phone number registration?

No. STIR/SHAKEN authenticates caller ID information within supported call paths. Phone number registration provides participating carrier or analytics databases with information about the legitimate business using the number.

Does STIR/SHAKEN replace telemarketing compliance?

No. Businesses remain responsible for applicable consent, calling-hour, suppression-list, privacy, recording, and industry-specific requirements.