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DIDChecks

What is Spam Likely on US Carriers?

Investigation into the STIR/SHAKEN labeling that destroys your B2B reputation.

SPAM
LIKELY

Carrier Network Alert
?

In brief: The algorithm's verdict

The "Spam Likely" alert is not human: it is the result of a STIR/SHAKEN attestation score. US carriers use STIR/SHAKEN protocol and apps like Hiya to identify repetitive call patterns, overly short call durations, and abnormally low answer rates.

The 6 culprits

1. Massive Volume

Too many calls made from the same number in too short a time frame.

2. Low Answer Rate

A "No Answer" rate above 80% is an immediate red flag.

3. User Reports

Users have manually blocked or marked you as unwanted on their phone.

4. Low STIR/SHAKEN Attestation

Your carrier assigns B or C attestation level instead of full A attestation.

5. Bad Timing

Calling during rest or meal hours increases the irritability rate.

6. Recycled Number

Your new number already had a bad reputation from its previous owner.

The "Spam Likely" Logic

Your Number
STIR/SHAKEN Check
Reputation Score
Alert Display
Carriers verify attestation and reputation in real-time via STIR/SHAKEN.

Carrier Comparison

CarrierAlert message displayed
Orange"Spam Risk" (Verizon)
SFR"Scam Likely" (T-Mobile)
Bouygues"Suspected Spam" (AT&T)
Free"Potential Spam" (US Cellular)

How to know if you're flagged?

Solution 1: DIY Method

Call a friend or colleague's phone on different carrier networks.

Cost: Free | Accuracy: Low

Solution 2: DIDChecks

Test your numbers on our pool of 500+ real devices across United States.

Cost: Professional | Accuracy: 100%

Prevention

  • - Number rotation every 2 hours
  • - TCPA-compliant opt-in list verification
  • - Compliance with legal calling hours (8am-9pm local)
  • - Non-aggressive call scripts

Reaction (If flagged)

  • - Immediate rest period (15 days)
  • - Removal request to Hiya/First Orion
  • - Get full A-attestation from carrier
  • - Delete number if persistent

Number Healing Time

Severity ScoreRecovery Time
Nuisance (70-80%)15 days (complete rest)
Negative (80-90%)30 days (complete rest)
Spam / Fraud (90%+)Change the number

Investigation questions

Can I pay carriers to remove the alert?
Not directly. Carriers rely on STIR/SHAKEN attestation and third-party analytics. However, you can register with Free Caller Registry or work with your carrier to improve your attestation level.
Does using a toll-free number protect against Spam Likely?
Actually, toll-free numbers (800, 888, etc.) are often MORE scrutinized because they're heavily used by robocallers and scammers.
"Spam likely" shows but I'm not telemarketing, why?
Several possible reasons: the previous owner of the number burned it, your carrier assigns low STIR/SHAKEN attestation, or you have a professional call volume (support, follow-ups) that looks like telemarketing to the algorithm.
Does it show on all phones?
No, only on phones with anti-spam protection enabled. But that represents 73% of US users, so the majority.
If I change my number, will the new one be clean?
Not necessarily. The new number may have been used before you. Always check a new number BEFORE using it in production.

Complete diagnosis in less than 30 seconds

Related guides

Why does nobody answer?

How long blacklisted?

Avoid spam flagging

Understanding STIR/SHAKEN

What is 'Spam Likely' on US Carriers? Why it shows and how to avoid it | HUHU.fr