Buying a number is usually two minutes — Settings → Phone Numbers → Add number, pick country, type, and area code. This article covers the two places people get stuck: inventory and compliance.
When no numbers show up
Number inventory fluctuates, especially toll-free (1-800/833/844/855/866/877/888). If your search comes up empty:
Search by city instead of prefix. City searches (e.g. Los Angeles, Miami) often surface local numbers that prefix searches miss.
Try nearby area codes. A neighboring code in the same region reads just as local to recipients.
Toll-free specifically: inventory refreshes; try again later the same day, or ask us in the chat and we'll check availability on our side.
After you buy: compliance before volume
A number can place calls immediately, but US/Canada SMS at any real volume requires registration first:
Local numbers → A2P 10DLC registration
Toll-free numbers → Toll-Free Verification (TFV)
Unregistered sending gets silently filtered by carriers — messages show "sent" but never arrive — so do this before your first campaign, not after.
The submission flow
Submit your business information at Settings → Phone (app.k3x.ai/settings/phone). You'll provide business identity details, your website, the use case, opt-in method, and sample messages. We start the verification process on our end as soon as you submit.
While you wait: registration typically takes days (see the A2P 10DLC guide and the TFV article for timelines and rejection fixes). Toll-free numbers can send a small trickle unverified — enough to test, not enough to campaign.
Costs recap
Local numbers are $1.15/month, toll-free $2/month, billed with your subscription. Porting an existing number in costs $15 one-time — see "Buy or port a phone number into K3X."
Stuck on availability or a rejected registration? Message us in the widget — number inventory and compliance are things we can often unblock same-day.