You're placing calls from K3X and your team starts noticing leads aren't answering. Some report their phone showed "Scam Likely", "Spam Risk", or "Telemarketer" when you called. Welcome to one of the most frustrating problems in outbound voice.
The good news: it's fixable. The not-so-good news: it takes a few moves, and prevention beats cure.
Why it happens.
US carriers (T-Mobile, AT&T, Verizon) use analytics engines to score every outbound call in real time. The engines look at things like:
How many calls your number is making per hour, day, week.
How many of those calls last less than 6 seconds (a heuristic for ignored/declined calls).
Complaint reports from recipients ("this caller is spam").
Whether the number is verified with industry analytics partners.
Whether the call passed STIR/SHAKEN attestation (a cryptographic signature that proves the calling number is allowed to use that caller ID).
A new K3X number with no reputation defaults to medium trust. If your team makes a lot of short calls early on, the score tanks fast — and once you're labeled, it sticks.
The fix, in order of impact.
1. Register for Voice Integrity (the most important step).
Voice Integrity is a service K3X uses to register your numbers with the analytics engines at T-Mobile, AT&T, and other major carriers. Registered numbers get higher baseline trust and are far less likely to be labeled spam.
Open Settings → Phone Numbers → [number] → Voice Integrity → Register. K3X asks for:
Your business name and address.
The use case for the number (sales outbound, customer support, etc.).
Your typical call volume and target geographies.
Registration is processed in 3–7 business days and costs $10/number/month, charged by the underlying registry. Worth it for any number doing meaningful outbound.
2. Turn on Branded Calling.
Branded Calling makes your business name appear on the recipient's screen when you call, instead of just the number. Major carriers now display branded calls with a verified badge that explicitly tells the recipient it's a legitimate business.
Setup is under the same Voice Integrity page. You upload your logo and the display name, K3X submits to the branded-calling networks, and you're live in ~2 weeks. Cost is $0.005 per branded call on top of the regular call rate.
3. Make sure STIR/SHAKEN is signing your calls.
STIR/SHAKEN is on by default for every K3X number — you don't need to do anything. You can verify on Settings → Phone Numbers → [number] → STIR/SHAKEN — the attestation level should read A (Full Attestation). If it reads B or C, contact K3X support; this should always be A for numbers you own.
Recipients on STIR/SHAKEN-compliant carriers see a checkmark or "Verified" indicator next to your caller ID for A-attested calls.
4. Slow down and lengthen your calls.
Carrier analytics treat very short calls as a spam signal. If your team is power-dialing 80 numbers a day and 60% of them last less than 10 seconds, your number's reputation will degrade no matter what else you do.
Aim for:
Calls that average >30 seconds (including voicemails and "wrong number" early hangs).
Volume that's consistent rather than spiky — 50 calls/day every day beats 250 calls one day and zero the next.
Spread across numbers if you're doing high volume — 5 numbers each doing 50 calls is better-tolerated than 1 number doing 250.
5. Don't reuse a burned number.
If a number has already been labeled, the label can take months to lift even after you fix the underlying behavior. Your fastest path to clean delivery is sometimes to release the bad number and start fresh with a new one (and register for Voice Integrity from day one this time).
Release from Settings → Phone Numbers → [number] → Release. The number goes back into the carrier pool and someone else gets it next; you can buy a new one immediately.
How to check your current reputation.
K3X surfaces a spam reputation score on each number's settings page, refreshed daily. It pulls from the same data carriers use. Green (above 80) = no concern. Yellow (50–80) = being watched; act on the steps above. Red (below 50) = actively labeled; consider releasing and starting over.
You can also test from your end: install a few free apps that show spam labels (Truecaller is one) on your personal phone, then call yourself from your K3X number to see what shows up.
What doesn't help.
Calling people from a different number. The label is attached to the calling number's reputation, not your business. Switching numbers without fixing behavior just creates a new bad reputation.
Asking recipients to remove the label. Recipients can't usually do this from their phone — the label comes from the carrier, not the recipient's contact list.
Filing complaints with the carrier. Verizon and AT&T don't have customer-facing reputation appeals. The analytics partners (and Voice Integrity registration) are the channel.
Next: CNAM and how your business name appears on caller ID →
