Healthcare Call Deliverability: STIR/SHAKEN, Spam Labels and Branded Caller ID

Why do legitimate healthcare calls go unanswered?

A hospital calls a patient two days after discharge to check on her recovery. She gave consent, and a clinician signed off on the call. By every compliance standard that matters, the call is in order. It arrives on her phone as "Spam Likely," her phone sends it straight to voicemail, and she never calls back. The hospital's dashboard shows an outreach program that ran. The patient's experience is that nobody called.

Most of the attention in patient outreach goes to what happens during the call: the script, the AI, the handoff, the consent record. All of it depends on an earlier step that now fails often, which is the call being delivered, trusted and answered in the first place. Industry data suggests roughly half of outbound calls are never answered at all, and only about a quarter of dials reach a live person. Hiya's State of the Call 2026 found that 86% of unidentified calls now go unanswered, and consumer survey data cited in Consig's Getting Through research finds 82% of Americans admit ignoring calls they actually wanted, up from 59% two years earlier.

Patients have good reason to be wary. Industry data suggests that in 2025, 38% of Americans received a call from someone impersonating a healthcare provider or insurer. So when an unfamiliar number rings, the patient's first thought is a reasonable one: how do I know this is really my doctor? A legitimate caller has to answer that question before the patient will pick up, and most of the machinery that decides how the call appears is outside the caller's hands.

In healthcare the cost of an unanswered call is clinical, not just operational. A blocked post-discharge call can mean an unfilled prescription or an unreported symptom. A blocked reminder can become a no-show. Deliverability failure converts directly into care gaps. At Plug and Play Orlando, Consig's CEO relayed what clinical leaders at GuideWell had described: a team of nurses dedicated to following up with high-risk members, and 75% of those patients never reached, because the nurses spend their days calling rather than connecting.

How do carriers label and block calls?

Between every outbound call and every handset sits a layer of labeling and blocking infrastructure that decides, before the phone rings, whether it rings at all. Carriers and their analytics partners score calls in real time on traffic patterns, complaint data and number reputation. Calls that score badly are labeled, with wording that varies by carrier and app ("Spam Likely," "Scam Likely," "Potential Spam," "Telemarketer"), or blocked outright. The TRACED Act explicitly empowered providers to block at the network level, with safe-harbor protection when they do.

For an organization doing legitimate calling, this produces a double loss. First, false positives from the labeling layer block real calls on a regular basis: survey data cited in Getting Through finds that 34% of Americans report having missed important calls because caller ID incorrectly flagged them as spam. Second, the caller is not reliably told which calls were labeled or blocked, or why. A program can lose a meaningful share of its reach without any error appearing in its own systems.

Labeling is only one of the gates. Consig's Getting Through research maps five layers that every call passes through before a patient decides to answer, and the caller owns none of them. Understanding who controls each layer is the starting point for any deliverability practice, because the remedies differ by layer.

Why does a normal healthcare calling pattern look like spam?

The uncomfortable finding in the Getting Through research is that the ordinary behavior of a healthcare calling program looks like spam to an analytics engine. Nothing about the program has to be wrong. The patterns that analytics models associate with unwanted calling are the same patterns that well-run outreach produces, and together they mean that a program can degrade its own number reputation simply by running as designed. That is why a compliant program is not automatically a reachable one.

Part of the reason is vocabulary: "robocall" is used loosely for any unwanted automated call, so legitimate healthcare calls are scored, labeled and blocked by the same carrier systems built to stop illegal ones. See what counts as a robocall.

The other part is visibility. Email deliverability has been a recognized discipline for twenty years, with dedicated teams, tools, feedback loops and vendors, and nobody running a marketing list would accept "we send them and hope." Voice deliverability affects a channel that is more expensive, more regulated and more clinically consequential, and most healthcare organizations still have little visibility into it. They can tell you how many calls they dialed. They usually cannot tell you how those calls displayed on a patient's screen, on which carriers, this week.

The four patterns to watch in your own program:

• High call volume from a single number. A team working through a discharge list or a care-gap cohort places many calls from the same line.
• Short call durations. Most attempts reach voicemail, so the average call is brief.
• Repeated attempts to numbers that never answer. Follow-up protocols call back patients who did not pick up the first time.
• Bursts of activity. A recall campaign concentrates volume into a short window.

What does STIR/SHAKEN do, and what doesn't it do?

Ask a health system how it handles call deliverability and you will often hear a version of the same answer: our carrier does STIR/SHAKEN, so we are covered. They are not covered. They are authenticated, which is a different and much smaller thing.

STIR/SHAKEN is the caller ID authentication framework the FCC has required of major U.S. voice providers since 2021, mandated under the TRACED Act to fight illegal spoofed robocalls. The originating provider signs each call at one of three attestation levels, and the terminating provider verifies the signature. The result is a cryptographic attestation that the call's originating number was not spoofed in transit. That is genuinely valuable. It is also the entire extent of the claim.

Authentication is not identity. STIR/SHAKEN can verify that a call genuinely comes from the number displayed. It says nothing about who that number belongs to, why they are calling, or whether the recipient should trust them. A patient looking at an unfamiliar ten-digit number gains nothing from knowing it is cryptographically genuine. She cannot see the signature. What she sees is an unknown number, and what she does is let it go to voicemail.

The gap is now measurable. Transaction Network Services analyzes call traffic for more than 150 carriers and also sells voice security and branded calling into the same market, so its numbers should be read with that in mind. Its mid-2026 report found that 17% of confirmed spoofed calls carried the highest "A"-level attestation, that invalid numbers (unallocated, not in use, or flagged Do Not Originate) were attested at "A" about 1.6% of the time, and that between 10% and 12% of traffic that passed verification was still tagged as unwanted.

The FCC's own record points the same way. In the Wireline Competition Bureau's December 2025 triennial report on STIR/SHAKEN, USTelecom told the Commission that some providers assign "A"-level attestation to calls that are "invalid, mis-formatted, unassigned, non-routable, or designated as Do Not Originate," and ZipDX called attestation "effectively meaningless." The Bureau did not conclude that the framework fails: it found the technology still effective at authenticating caller ID and declined to revise or replace it. Both things are true at once. The cryptography works, and a call that passes it is still not a call the patient has any reason to answer.

Coverage has a physical limit as well. STIR/SHAKEN works only where calls stay on IP networks. Where a call crosses a legacy TDM or SS7 segment, the authentication data is stripped in transit, and the FCC calls those non-IP segments the largest obstacle to universal coverage. The practical conclusion is that STIR/SHAKEN is table stakes, not a deliverability strategy.

What are attestation levels?

When an originating provider signs a call, it assigns one of three grades of confidence. The grade reflects what the provider knows about the customer placing the call and that customer's right to use the calling number.

Full attestation is a baseline trust signal and a prerequisite for most branded calling programs, so legitimate callers should structure carrier relationships so their calls sign at "A" rather than partial or gateway. It is also unevenly available. Industry data suggests the seven largest U.S. carriers have plateaued at roughly 85% signed traffic between networks, up a single point in a year, while smaller carriers sit near 20%. And a signature applied correctly at origin does not always survive the trip, because of the TDM and SS7 stripping described above.

Attestation is also under regulatory review. The FCC has proposed tying Know-Your-Customer diligence to attestation decisions, so that whether a provider may sign a call at "A" level would depend partly on whether it actually knows who the customer is. That proposal is a concession that a signature, on its own, has not been sufficient evidence of identity.

What is number reputation and why is it perishable?

Number reputation is the trust score that carriers and call-analytics engines assign to a calling phone number. It determines whether that number's calls ring normally, display a spam label or are blocked. Reputation is built from signals such as call volume, answer and complaint rates, call duration, and whether the number has been reported or spoofed, which is why the calling patterns described above wear it down.

Spoofing deserves particular attention. If a scammer places calls using a health system's numbers or name, the complaints and labels attach to the legitimate caller. Regulators are also scrutinizing the opposite tactic from the legitimate side: an FCC proceeding on numbering addresses the practice of churning through large blocks of numbers to stay ahead of analytics and blocking. Retiring a burned number is remediation. Cycling numbers to outrun the analytics is the behavior the proceeding targets.

Reputation is perishable. Carrier algorithms retrain, labels drift, and a number that is clean today can be flagged next month without the caller being notified. That makes reputation a monitoring loop, not a setup task. A serious practice does four things continuously:

• Registers calling numbers with the major carriers' analytics providers.
• Monitors how every number displays across carriers, and detects a "Spam Likely" label within hours rather than weeks.
• Remediates, including rotating or retiring numbers that have been burned.
• Watches for spoofing of its own numbers and name, because a scammer's abuse of your identity becomes your reputation problem.

What is branded caller ID and does it work?

Branded caller ID displays a verified business name, and increasingly its logo and call reason, on the recipient's screen when that business calls. It addresses the gap STIR/SHAKEN leaves open: a patient cannot see a cryptographic signature, but she can see "City Hospital, Post-discharge check-in." Branding is delivered through each carrier's separate program and typically requires vetting of the business, registered numbers and full attestation. Rich Call Data (RCD) is the identity extension to STIR/SHAKEN that carries this information.

Branding is distinct from CNAM, the short caller ID name of up to 15 characters that a recipient's carrier typically looks up in a CNAM database rather than receiving with the call. CNAM is not authenticated, coverage across wireless carriers and handsets is inconsistent, names are often truncated or stale, and a carrier spam label or the handset's contact list can displace it. CNAM registration is one layer of a display strategy, not the whole of it.

Does branding work? The evidence that identity drives answers is strong: industry data suggests 78% of consumers say a verified business logo would make them more likely to pick up. That is a stated preference rather than a measured answer rate, and the sources this guide draws on do not quantify a typical lift. What they do establish is the direction of travel. The trust problem runs in both directions, and identity has to be earned in every channel: texting a patient a link to click can feel more like a scam, not less, so verified sender identity matters on messaging as much as on voice.

Consig uses branded, verified caller ID, with Know-Your-Customer checks behind the number, so its customers' names show up on the patient's screen and more calls get answered rather than screened. Caller ID and number reputation are handled behind the scenes through carrier relationships and strategic partnerships, and numbers, dialing, branded caller ID and reputation management come with the platform rather than through a separate CPaaS contract. See integrations.

How do AI call screeners change outbound calling?

AI call screening adds a gate after carrier labeling. Google's Call Screen on Pixel phones and Apple's call screening in iOS 26 both intercept calls from unknown numbers, ask the caller for a name and reason, and transcribe the reply so the owner can decide whether to pick up. AI screeners on most U.S. handsets now question callers before a human hears anything. A legitimate call can be delivered, correctly identified and still never reach the patient, because nothing on the line answered the screener's question in a way the patient trusted.

For automated outreach this changes the first seconds of every call. A screener is an outcome distinct from both a person and a voicemail box, and it is interactive. A calling system now has to recognize whether it has reached a person, an answering machine or an automated screener; respond to a screener appropriately, stating who is calling and why; and fall back to a voicemail or retry strategy when the screener does not put the call through.

The screener is also, in effect, the patient's first impression of the caller. Whatever the system says to it is what the patient reads on the screen before deciding. That is why screener-aware calling sits alongside reputation management and branding as part of one deliverability practice rather than as a separate feature.

In a live demo at Plug and Play Orlando, Consig's agent navigated call screeners before verifying the patient's identity with Face ID and continuing the call through information collection and handoff to the care team. Consig describes its outreach engine as automating the painful part of outreach, including voicemails, follow-ups, call screening and incomplete interactions, so staff can concentrate on the calls that lead to clinical conversations.

How should you measure deliverability honestly?

Outbound metrics form a funnel, and most dashboards report its widest end. Dials lead to answered calls. Some answered calls reach a live person rather than voicemail or an automated screener. Some of those people are the intended contact, confirmed as such. The last step is the right-party contact (RPC) rate, and it is the one that tells you whether outreach reached patients.

Definitions vary between organizations and vendors, especially over whether answering machines count as answers and whether "right party" requires formal identity verification. Rates are only comparable when the denominators match, so agree the definitions before comparing programs, vendors or carriers. A program that reports "calls completed" may be counting voicemails and screener exchanges alongside conversations.

RPC depends on list quality as well as display. Numbers change hands, and under the TCPA consent comes from the current subscriber, so calling a reassigned number can be a violation even when the original consent was valid. The FCC's Reassigned Numbers Database, available to callers since November 2021, offers a safe harbor for callers who query it properly. In healthcare, reaching the right party also matters because identity has to be confirmed before protected health information is discussed, and for programs such as Transitional Care Management the share of an eligible cohort actually reached inside the required window determines both clinical value and revenue.

Measurement is also how you evaluate vendors. Two outbound systems can sound identical in a demo and differ by double digits in real-world answer rates, because the difference lives in carrier relationships and reputation operations rather than in the conversation. Ask for funnel numbers with stated definitions, broken out by carrier, rather than a demo call.

What does a deliverability practice look like week to week?

Because reputation is perishable and the caller is not told when a label appears, deliverability is a standing operation rather than a project. The cadence below draws on the components the Getting Through research sets out. Some steps are continuous, some belong in a weekly review, and some come up when a campaign is planned.

Calling windows belong in the same routine. Federal rules prohibit telephone solicitations before 8 a.m. or after 9 p.m. in the called party's local time, several states are stricter, and many healthcare programs apply a window like this to all outbound contact. A phone number no longer reliably shows where a person is, so a cautious approach checks both the patient's address of record and the number's area code; see calling-hour restrictions. A workable cadence looks like this:

• Continuously: monitor how every calling number displays across carriers, and treat a new "Spam Likely" label as an incident to resolve within hours.
• Continuously: pace attempts so volume patterns stay within what analytics engines tolerate, and watch for your own numbers and name being spoofed.
• Weekly: review the funnel by carrier (answer, live-contact and right-party contact rates) against the same definitions every week.
• Weekly: review screener and voicemail outcomes, and listen to how the system identifies itself when it meets a screener.
• Weekly: decide which numbers to remediate, rotate or retire, and confirm that new numbers are registered with analytics providers before they carry volume.
• Before each campaign: confirm attestation and branded caller ID coverage for the numbers involved, check the list for reassigned numbers and calling windows, and spread the campaign so it does not arrive as a single burst.

Should you run deliverability in-house or through a platform?

Platforms that embed outbound calling face a build-or-buy choice. A CPaaS gives developers programmable building blocks such as numbers, call control and APIs, and that suits teams that want to build and run the whole calling layer themselves. But a CPaaS can place a call without making it trusted: number and reputation management, branded caller ID, screener handling and the monitoring loop described above are left to the team that builds on it. See Consig vs. CPaaS.

Whichever route you take, the work is the same, and so is the test: can you say how your calls displayed on patients' screens, on which carriers, this week? If the answer is no, the gap is operational, not technical, and it will not close on its own.

Consig handles dialing patterns, reputation management and caller ID behind the scenes, through carrier relationships and strategic partnerships, so customers do not run carrier registration or monitoring themselves. Once a patient answers, identity is verified through a Zero Knowledge Network, with passkeys, device biometrics or one-time passcodes, so credentials never enter the AI or the transcript. See security.

Where is deliverability regulation heading?

Toward verified identity. In October 2025 the FCC adopted a Further Notice of Proposed Rulemaking on call branding, proposing to require voice providers to display verified caller identity (name, logo and call reason) using Rich Call Data. The proceeding acknowledges outright that attestation alone has not given consumers a reason to answer.

The months since have made the direction plainer. In April 2026 the Commission proposed enhanced Know-Your-Customer rules for the providers that originate calls: what they must collect from a calling customer, how they must verify it, how long they must keep the record, and when a shift in traffic patterns should force them to check again. A Know-Your-Upstream-Provider proposal followed in May, applying the same idea one step further down the call path. A third proceeding takes on telephone numbering itself, including the churning of large number blocks to stay ahead of analytics and blocking. And the Commission has proposed tying that diligence to attestation decisions.

The details are still being contested: which providers are covered, on what timeline, with what verification. The direction is not. Verified identity on the call is moving from competitive advantage toward regulatory expectation. Organizations building branded, reputation-managed calling now are aligning with where the network is headed. For the argument in full, read STIR/SHAKEN Proved Your Number Is Real. It Didn't Get You Answered.