Free tools / Number Portability Check
Number portability check
Around a third of US phone numbers no longer belong to the carrier that originally issued them. Every one of those numbers breaks any tool that infers the carrier from the area code and prefix. This check looks the number up in the portability database itself and tells you the carrier serving it now.
For telecom and messaging teams the interesting fields are the Location Routing Number (LRN), the Operating Company Number (OCN), the SPID and the port date. Those come back on every API call. The free page shows the current carrier, line type and rate center so you can confirm a port happened.
What you get back
Current carrier. Who serves the number today, which is the answer a prefix table cannot give.
Line type. Whether the ported number is now a mobile, landline or VoIP line.
Ported status and date (API). Whether the number has ever been ported and when the last port completed.
LRN and OCN (API). The routing number and carrier code you need for call routing, rating and SMS route selection.
How to use it
- Enter the number.
- Press Check porting. We query the live database, so ports from the last few days are reflected.
- Compare the carrier to what your records say. If they differ, the number was ported and your records are stale.
Who uses this
Carriers and VoIP providers. LRN dips before routing every call is standard practice, and this is the same data at a per-lookup price with no minimum.
SMS aggregators. Route selection by OCN avoids sending into the wrong carrier gateway.
Data teams refreshing old lists. A list built years ago has carrier fields that are wrong for every ported number. One pass through the API fixes it.
Same check, in your code
One API key, one credit pool, 1,000 free lookups to start. Phone, email, IP and DNS checks from a single endpoint, and you only pay for lookups that return an answer.
Start free Read the docsQuestions
What is an LRN?
Location Routing Number. A ten-digit number that identifies the switch now serving a ported number. Networks route to the LRN instead of the dialed number.
Why is the port date empty?
Numbers that have never been ported have no port date. On the free page the field is locked; on the API it returns null for never-ported numbers.
Does this cover Canada?
Yes, US and Canadian numbers are both in the portability data we query.
How fresh is the data?
We query live and cache each number for seven days to keep your cost down. A port that completes inside that window shows on the next uncached lookup.
Is this the same as an HLR lookup?
No. Portability tells you which carrier owns the number. HLR asks the mobile network whether the handset is currently reachable. HLR is a separate product on paid plans.