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Every phone number carries a reputation with the phone networks. Carriers score how a number behaves, and that score decides whether your call rings normally or arrives labeled Spam Likely on your customer’s screen.
If you make a lot of outbound calls, expect this early on. A new number has no calling history, so carriers have nothing to judge it by. Numbers that start out with high outbound volume are likely to pick up a spam label in their first weeks. This is not a fault in your setup, and it is not something Allo turns on or off. Real conversations are what clear it.

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Two systems, two different jobs

People often treat authentication and reputation as one thing. They are scored separately, by different parties. Every call you place through Allo is signed with full A-level attestation, verified at our number provider. That does not change from one call to the next, and it is the strongest signal a provider can attach to a call. Authentication proves you are not spoofing a number you do not own. It says nothing about whether people want to hear from you. That second question is reputation, and it is where spam labels come from. A number can be fully authenticated and still show a spam label.
Allo calls are signed at A. STIR/SHAKEN is a US and Canadian framework, and other countries run their own anti-fraud systems.

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What carriers actually score

Carriers and the screening apps installed on your customers’ phones (Hiya, Truecaller) watch how a number behaves. Those signals propagate between networks, which is why the same number can look clean on one carrier and flagged on another. None of these is a switch. Each one nudges a score that carriers recalculate on their own schedule.

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Warming up a number

Warming up means giving a new number enough real calling history that carriers stop treating it as unknown. There is no shortcut, because the thing being measured is how the number behaves.
1

Set your caller ID name first

A registered business name gives carriers a trust signal from day one, and gives the person a reason to answer.
2

Start below your target volume

Build up over several days instead of dialing your full list on day one. A quiet number that suddenly places hundreds of calls can trip an algorithm on the spike alone.
3

Aim for conversations, not attempts

Answered calls of a normal length are the signal that lifts a score. A high ratio of unanswered, very short calls is the signal that hurts it.
4

Text before you call

A short heads-up text (“Hi, this is Sam from Smith Plumbing, calling you in 5 minutes about your quote”) lifts answer rates and makes a spam report less likely.
5

Spread heavy volume across more than one number

If your outbound volume is high, split it across several lines rather than pushing everything through one.
6

Keep your list clean

Remove disconnected and wrong numbers, and stop calling people who asked you to. Repeatedly dialing dead lines is a classic spam signal.
Reputation follows behavior. As your number becomes associated with a real business having real conversations, the label becomes less likely to stick.

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Your caller ID name

Your caller ID name (CNAM) is the business name shown next to your number when you call a US or Canadian number. You set it yourself in Settings > Numbers, in the Number reputation section.
  • 15 characters maximum, so pick a short form of your business name
  • Up to 72 hours to propagate across all carriers
  • US and Canadian numbers only

Set your caller ID name

The rules, the character limit, and how to fix a wrong name

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Frequently asked questions

There is no switch that clears a label. Carriers score a number on how it behaves, so the fix is to change what the number does and give the score time to catch up:
  • Register your caller ID name if you have not already
  • Bring your daily volume down for a while
  • Prioritize calls that turn into conversations over raw dial count
  • Remove disconnected and wrong numbers from your list
A label that reflects a real calling pattern comes back if the pattern stays the same. This is why the answer is behavior rather than a one-time action.
No, and it usually costs you. A new number resets its history to zero, which is not the same as a good reputation: carriers treat an unknown number with suspicion, so you start the warming period again from the beginning. You also lose a number your customers recognize and may have saved.If the calling pattern that triggered the label has not changed, the new number ends up in the same place.
Partly, and it depends on why you are rotating.Spreading volume across a few numbers helps. Splitting heavy outbound across several lines keeps any single number below the burst pattern that trips an algorithm.Rotating to outrun a label does not work. Each number builds its own reputation from its own behavior, so if the calling pattern is what caused the label, every number in the rotation picks one up in turn. Cycling through many numbers also works against you, because a number with thin history has nothing vouching for it and stays unknown.Use a few numbers, warm each one, and keep them. Do not treat numbers as disposable.
Call a few phones on different carriers and look at what shows on screen. A label lives with the recipient’s network, not on your line, which is why the same number can look clean on one carrier and flagged on another. If a customer mentions a specific screening app, ask them which one, since each app scores separately.
No. Allo never labels your own number. The labels are applied by phone carriers.
Carriers recalculate scores on their own schedule, so expect the change to show over weeks rather than days, and only if the calling pattern behind the label has changed. A number with a long history of complaints takes longer.
Carriers do not publish thresholds, and there is no figure that holds across every network. What they weigh is the shape of the traffic rather than the raw count: how many of your calls get answered, how long they last, and how many land on dead or wrong numbers. A high volume that mostly turns into conversations looks healthier than a much smaller volume that all goes unanswered.
The tool is not the signal, the pattern is. A carrier cannot tell whether a number was dialed by hand or from a queue. What it sees is volume, answer rate, and call length.A dialer does make the risky pattern easier to produce, because it removes the natural pacing of dialing by hand. Pace your sessions and watch how many calls actually connect.
STIR/SHAKEN is specific to the US and Canada. Most other countries run their own caller-reputation and anti-fraud systems, and the calling habits that build a good reputation are the same everywhere.

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Where to go next

Caller ID Name (CNAM)

Display your business name on US and Canadian calls

Buy additional numbers

Add lines to spread out heavy outbound volume

SMS & messaging

Text a customer before you call them

Understand your Allo number

How your business number works on Allo