identifierNumber
+12345678900The number as the API returns it, in E.164.
Find the original carrier behind a number, in real time
Submit one number and the same response returns its original allocation: carrier, line type, country and allocation region. Explore the fields before you integrate.
$0.001 per completed lookupFailed or undetermined lookups are refundedFree demo lookup · no account needed
Real-time carrier lookup
Illustrative sample · not a live lookup
Original carrierT-Mobile
- Number
- +12345678900
- Number type
- Fixed Line or Mobile
- Country
- US
- Region
- OH
- City
- AKRON
Where does one carrier lookup fit into real work?
The same number can raise different questions for sales operations, messaging, risk, and telecom data teams. Here is what this result can help each team do.
The fields teams actually receive
Add carrier, country, region, and line-type context to an existing record. Sales, messaging, and risk teams can use the same result to spot mismatches, prioritize review, and choose the next step.
From a fixed CarrierLookup test sample; unavailable fields are marked as not returned.- identifier
- +12345678900
- carrier
- T-Mobile
- underlying_carrier
- Not returned
- number_type
- Fixed Line or Mobile
- country_code
- US
- region
- OH
- city
- AKRON
Four teams, four next steps
The same lookup fields can move four different teams forward once they become part of a working record. These are illustrative business workflows.
Give sales a more complete lead record
A campaign lead gives Canada in the form and leaves this phone number. Before handoff, the CRM needs the submitted details and number context on the same record.
Use the result
Keep Canada as the submitted country. Add T-Mobile, US, OH and AKRON to separate number-context fields so sales can decide how to route and approach the lead.
Record the next step
Save the lookup source and time with the handoff. Sales can clarify the market during first contact and update lead ownership without overwriting the customer’s answer.
Your working recordCRM lead · before handoff
Team record
- Phone number
- +12345678900
- Form country
- Canada
Lookup fields used here
- Original carrier
- T-Mobile
- Allocation country
- US
- Region / city
- OH · AKRON
Team next stepSales to review lead details
At handoff, sales compares the submitted Canada value with allocation country US, confirms the target market and owner, then keeps both values and the lookup time on the CRM lead before updating its assignment.
Lookup fields come from a real test sample. Existing team data and follow-up actions illustrate possible workflows.
From record enrichment to task assignment, these fields help teams spot differences, record the evidence, and move the next review forward.
Explore detailed work examplesWhat a carrier lookup returns
Use the returned carrier, number type and location fields to organize phone records.
POST /api/v1/check200 OKnumber_typeNumber type
Fixed Line or MobileLine type as the provider reports it — for US numbers it is usually “Fixed Line or Mobile”, which does not separate the two.
country_codeCountry code
USTwo-letter ISO country code.
carrierOriginal carrier
T-MobileCarrier the number was originally allocated to. Not the current carrier after porting.
regionRegion
OHAllocation region — a state or province code. Can be empty.
cityCity
AKRONAllocation city as the provider writes it; sometimes an exchange code rather than a place name. Never a live location.
An empty optional field does not make a lookup invalid.See field guidance →
A lookup is only useful when the next step is clear
See one number move from a team discussion into a record with carrier context.
The number is there. The carrier field is empty.
Maya’s team receives a phone list to organize. It contains numbers but little context for the handoff. She checks one number first and places its original carrier and country code beside it so a colleague can continue the review and grouping.
Verified lookup sample
- phone
- +12345678900
- carrier
- T-Mobile
- country_code
- US
What goes into the handoff?
Read the full storyKeep the original number, add carrier and country_code as separate columns, and note the lookup source. The next teammate can see T-Mobile and US before deciding which records need another check.
Free generation · no charge until you submit a check
Free generatorFrom a generated list to a ready-to-use result
Create your list for free, choose what to check, then download the completed results.
Generate a listChoose your settings and create a candidate list.
Review the fileReview the generated file and select a check.
Run the checkConfirm the product and task details before submitting.
Download resultsTrack the task and download its result file when complete.
generated-list.csvYour generated list
ReadyIllustrative input · 6 sample rows
121355501011213555010212135550103121355501041213555010512135550106
Ready
Global carrier lookupidentifier12135550101carrierT-Mobileunderlying_carrier""number_typeFixed Line or Mobilecountry_codeUSregionCAcityLOS ANGELES
Illustrative result preview: Global carrier lookupDownload CSV
How to call the real-time carrier lookup API
Review the single-number request and the typed response, then call the same endpoint with your own API key.
Original allocation only. No current-carrier, reachability or real-time location claim.
Read API documentationcurl "https://api.carrierlookup.online/api/v1/check" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{"service_type":"carrier",
"identifier":"+12345678900"}'Carrier lookup pricing
Pay for what you check — no subscription required. One balance covers every check you run.
Permanent top-up
$19.90
Balance credited$19.90
Balance never expires. Use it across every product in your account.
See all plans →30-day plans
$9.90
Balance credited$10.40
Same spend, more bonus balance. Renews every 30 days.
See all plans →
Reconcile a Carrier Bulk Task Reservation with Its Final ChargeSeparate reserved balance, completed results and released reserve, then explain differences when other work shares the same wallet.Read article
Test a Carrier Lookup Integration Offline with Response FixturesTest flat carrier fields, empty results, ordered multi responses and error branches without real contact data or paid API calls.Read article
Test Original Carrier Enrichment on a Sample of Your CRM Phone DataRun an original-carrier enrichment pilot with a representative phone sample, field-level reference checks and an honest scorecard for unknowns and review work.Read article
Phone Number Validation vs Activity Check: Pick the Right File TaskChoose CarrierLookup number validation or number activity by the question the team needs answered, and read activated only with its selected product context.Read article
Carrier Lookup MCP vs REST API: Choose the Right WorkflowChoose an interactive MCP carrier check, a synchronous REST request, or an asynchronous file task based on list size, review, and audit needs.Read article
Carrier Lookup, HLR or Format Validation: Choose the Phone Data You NeedChoose format checks, original-carrier data, HLR-style network information or possession verification by the question your workflow must answer.Read articleCarrier lookup FAQ
Answers on carrier data, balance, API access, and failed lookups.
How do I find out which carrier a number belongs to?
Submit one number in E.164 form and CarrierLookup returns the network it was originally allocated to in the same response, as top-level fields of the result. There is no task queue, no polling and no callbacks. Nothing is ever sent to the number.
Is the carrier lookup real time?
The lookup is real time; the data is original allocation — keep the two apart. Once a number is submitted, the result comes back in the same HTTP response as top-level fields, with no task queue, no polling and no callbacks. What it returns is the network that number range was originally allocated to. It does not follow number portability, so it is not necessarily the carrier serving the number today, and it says nothing about whether the number is reachable. The dashboard, the single-number API and the synchronous multi-number API all return the same fields.
How is balance charged?
Permanent balance is a one-time purchase and does not renew. 30-day plan balance is valid for 30 days from payment; unused balance expires at the end of the current cycle. Plans renew automatically every 30 days until you turn off auto-renewal. Turning it off stops future charges; the current plan stays usable until it expires. Checks that fail or are undetermined are refunded to the relevant wallet.
How do I get the 100 free checks?
Create a free account and contact support to get 100 free checks. You can top up at any time.
Which payment methods are supported?
Permanent top-ups can be paid by credit card, other supported card payments, or cryptocurrency. 30-day plans use secure hosted card checkout and renew every 30 days. Card payments carry no extra fee. Cryptocurrency may include a service fee, shown at checkout.
How do I call the CarrierLookup API?
Create an API key in Settings, then call /api/v1/check with the X-API-Key header, a number and service_type=carrier. The carrier data comes back in that same JSON response as top-level fields — carrier, underlying_carrier, number_type, country_code, region and city; several numbers can be sent together through the synchronous multi endpoint.
Does a carrier result mean the number is active and reachable?
No. A result only reports the network a number was originally allocated to. It does not follow number portability and does not mean the number is currently reachable. You remain responsible for consent and applicable rules before contacting anyone.
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