How Do Numbers End Up Flagged as Spam?

Phone numbers receive flags in two ways:

  • By carriers

  • By consumers

Carriers Flagging Numbers

Most carriers have built-in thresholds that monitor call volumes for suspicious activity. If a single phone number is making more than a certain amount of calls a minute/day/week, carriers may determine that this activity is not originating from human dialing, or is spam. In these instances, the carrier can assign a flag score to your number indicating that it is likely robocalling/spam.

Consumers Flagging Numbers

While adjusting your dialing practices can reduce the risk of carrier flags, consumers are ultimately still able to manually block/report numbers via call blocking apps/tools.

With "scam likely" caller ID tools, one block/report will likely not lead to a flag on your number. However, if a tool sees that your phone number has received multiple blocks/reports, it will label your number as either a “nuisance call,” “spam call,” or “scam likely.”

Typically, call blocking apps/tools only work with particular carriers, meaning if your number gets flagged on a particular tool, your caller ID may only show “scam likely” on some carriers.

Erroneous Number Flagging

Should a scammer "spoof" your number, their activity may cause your number to erroneously become flagged as spam.

In some instances, consumers who simply do not like your brand may block/report your number as well, causing it to be flagged.

How to Deal with Flagged Numbers

As the carriers and third-parties creating/monitoring these thresholds and apps/tools are looking to protect consumers, there is not a clear system in place at the moment for businesses to dispute flags. A business can attempt contacting carriers or call blocking apps directly to dispute a flag, however communication is often difficult with few results.


The best way to deal with flagged numbers is to prevent flags from occurring in the first place if possible. This means being mindful of your calling behaviors to ensure you are not making too many calls on each number and thus being flagged automatically by carriers.

Some recommendations high-volume call centers can use to help avoid numbers getting flagged as "scam likely" are:

  • Limit the amount of times you call the same number each day. For example, calling the same Lead 10 times each day could result in a flag.

  • Try to minimize the amount of times you hang up on the people you are calling. Maintaining a less than 3% drop rate could help prevent a flag.

  • Make sure the people you are calling can reach you if they call back.

Another recommendation for US numbers is to register them at:

After entering some information about your company and numbers, the Free Caller Registry will submit that information to the Analytics Engines wireless carriers work with, in order to help prevent flags.

Letting Your Numbers Cool Off

When a number becomes flagged, halting its use can be beneficial in avoiding it affecting your business or obtaining more flags. Ceasing use of a flagged number for a while may also allow the flags to be removed over time, so keeping additional numbers that can be swapped out to replace flagged ones is a good idea.

Exceptional Cases

Due to phone numbers being repurposed by carriers, there is a possibility that some numbers purchased through Aircall may already be flagged due to a previous owner's activity. In this case, purchasing a replacement number via the Admin Dashboard is typically the quickest solution, however, a special ticket can be opened with the carriers we work with to ask for a new and unused number. While this is often not necessary, if you would like to move forward with this kind of ticket with our carriers, please reach out to our Porting Team.

Should you feel that your number has been marked incorrectly as Spam, please do feel free to reach out to the Support Team for assistance. Note that while the Support Team can discuss issues of your Caller ID showing as Spam with our carriers, there is often little that can be done once a number has been flagged. Should the Support Team get confirmation from the carrier that any possible changes have been made, we will not be able to further assist, and purchasing a new number may be necessary.

Still in need of assistance? Please feel free to reach out to the Support Team and

we will be happy to assist!

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