Why your number shows up as SPAM (and how to fix it)

— 3 min read —While carriers, third-party services and apps are getting better at detecting SPAM callers, some legitimate callers are left being burned by incorrect SPAM flagging. Here’s how to stay proactive and get your numbers unflagged.A suspected spam caller.

Have you noticed a drop in answered calls from your customers lately? Your business number could very well be flagged as SPAM by network carriers and SPAM filtering third-party services and apps. Numbers that are flagged may even be displayed as “SPAM LIKELY”, “SPAM RISK” or “SCAM LIKELY” to your customers before they answer your call.

Why are my numbers being flagged as SPAM?

Every time your business makes a call to a potential or existing customer, the customer’s phone carrier matches your number against a list of numbers they’ve determined to be SPAM numbers. Numbers are added to this list based on their history, customer complaints and other analytics from scam ID technologies.

Some common reasons that numbers are flagged as SPAM include:

1. A high volume of outbound calls per day by a single number

Carrier’s analytics software can’t always detect whether a number is legitimate or from a robot. The higher the volume of calls from a number, the more suspicious it appears. Generally, more than 100 calls per day from a single number will be viewed as suspicious.

2. Somone reported a number to its carrier as SPAM

Unfortunately, more and more numbers are being reported as SPAM due to increases in spoofing. Spoofing is when a caller disguises their caller ID as coming from a local number or company that the recipient may trust. Robocallers may be masking their identity under the name of your business, lowering the chance of customers accepting your calls.

3. Incorrectly set caller IDs

If your numbers’ outbound caller IDs have not been correctly set, they could likely be flagged automatically as spam by carriers’ SPAM detection algorithms.

Carriers also have various features and apps that are automatically enabled on mobile devices to display incoming call numbers that have been previously reported for SPAM as “Scam Likely”.

In some cases, customers may also opt-in to extra protective features that prevent calls flagged as “Scam Likely” from even reaching their phone.

Unfortunately, these lists of “SPAM” numbers reported are Carrier-specific. There is no central body or service that oversees number designation, which can make getting a number unflagged not such a straightforward process.

How to keep your numbers from being labeled as SPAM

The best way to keep your numbers from being incorrectly marked as SPAM is by being proactive. Businesses can get their number whitelisted among the top U.S carriers (AT&T, T-Mobile and Verizon) by registering their numbers with the Free Caller Registry. By registering, businesses are often able to avoid having their numbers flagged as SPAM for the three reasons mentioned above.

How to get your SPAM labeled numbers unflagged

As mentioned above, each Carrier and third-party SPAM blocking service/app has its own list of numbers marked as SPAM. Use the following links to register your numbers with these carriers and services and appeal to have incorrectly flagged or blocked numbers unflagged or unblocked.

Major carriers


T-Mobile, Sprint (1st Orion)

Verizon, U.S. Cellular (TNS)

Popular Spam Blocking Apps

Robokiller is used by millions to block spam callers. Once a number is reported by a single user, it will be automatically be blocked from all other users. Email their support to unflag your number.

Nomorobo is another popular SPAM blocking app and winner of the FTC robocall challenge. To contact them, email

Numbers on Icehook’s list are flagged as SPAM if they reach a risk level of 81-100.

Numbers on Truespam’s list are flagged as SPAM if they reach a score of over 60.