Carrier Lookup (original carrier) API

Carrier Lookup

The carrier originally assigned a US number block: company name, operating company number (OCN), rate center and state, from the public NANPA central office code and thousands-block reports, with the report date.

Get API key Read the docs

POST/v1/carrier-lookup

1curl -X POST https://YOUR_API_HOST/v1/carrier-lookup \
2  -H "Authorization: Bearer $LOOKVALID_API_KEY" \
3  -H "Content-Type: application/json" \
4  -d '{"phone":"+12024561111"}'

Read docs

POST/v1/carrier-lookup

1const response = await fetch("https://YOUR_API_HOST/v1/carrier-lookup", {
2  method: "POST",
3  headers: {
4    Authorization: `Bearer ${process.env.LOOKVALID_API_KEY}`,
5    "Content-Type": "application/json",
6  },
7  body: JSON.stringify({
8    "phone": "+12024561111"
9  }),
10});
11const result = await response.json();
12console.log(result.found, result.data);

Read docs

POST/v1/carrier-lookup

1import os
2import requests
3
4response = requests.post(
5    "https://YOUR_API_HOST/v1/carrier-lookup",
6    headers={"Authorization": f"Bearer {os.environ['LOOKVALID_API_KEY']}"},
7    json={
8        "phone": "+12024561111"
9    },
10)
11result = response.json()
12print(result["found"], result["data"])

Read docs

200Captured example, 2026-10-18

1{
2  "product": "carrier-lookup",
3  "found": true,
4  "data": {
5    "phone_e164": "+12024561111",
6    "npa_nxx_block": {
7      "npa": "202",
8      "nxx": "456",
9      "block": "1"
10    },
11    "original_carrier": {
12      "company": "VERIZON WASHINGTON DC, INC.",
13      "ocn": "9211",
14      "ocn_category": null
15    },
16    "rate_center": "WSHNGTNZN1",
17    "state": "DC",
18    "assignment_level": "central_office_code",
19    "code_holder": {
20      "company": "VERIZON WASHINGTON DC, INC.",
21      "ocn": "9211"
22    },
23    "in_service": true,
24    "assigned_since": null,
25    "line_type": "unknown",
26    "line_type_basis": "carrier name keywords, not an official category",
27    "ported": "unknown",
28    "data_date": "2026-10-17",
29    "blocks_data_date": "2026-10-17",
30    "notes": "This is the carrier the number block was originally assigned to. Number porting is not reflected (ported: unknown), so a number moved to another carrier still shows its original one. Line type is a hint from the carrier name only. Data is from the NANPA public reports and is not complete for routing or billing."
31  },
32  "sources": [
33    "North American Numbering Plan Administrator (nanpa.com) central office code report of 2026-10-17 and thousands-block report of 2026-10-17"
34  ]
35}

A real run of this lookup on 2026-10-18, using a public input. The envelope fields are left out.Read docs

1 credit per lookup (numbers outside the covered numbering plan areas are free)
Charged only when it finds something
Cached 7 days

1 credit per lookup (numbers outside the covered numbering plan areas are free)

Charged only when it finds something. A repeat inside 7 days is free.

Every LookValid product draws on one shared balance. See pricing.

From key to answer in three steps

One key, one POST to /v1/carrier-lookup and a JSON answer back. The same three steps work in any language that can send HTTPS.

01
Create a key
Sign up and copy a key from the dashboard. The same key works for every LookValid product and for the MCP server.
Terminal
```
export LOOKVALID_API_KEY="lv_live_..."
```

Send the request

POST a JSON body to /v1/carrier-lookup. 1 credit per lookup (numbers outside the covered numbering plan areas are free).

request.sh

1curl -X POST https://YOUR_API_HOST/v1/carrier-lookup \
2  -H "Authorization: Bearer $LOOKVALID_API_KEY" \
3  -H "Content-Type: application/json" \
4  -d '{"phone":"+12024561111"}'

Read the answer

A real run of this lookup on 2026-10-18. The data object has 15 named fields.

response.json

1{
2  "product": "carrier-lookup",
3  "found": true,
4  "data": {
5    "phone_e164": "+12024561111",
6    "npa_nxx_block": {
7      "npa": "202",
8      "nxx": "456",
9      "block": "1"
10    },
11    "original_carrier": {
12      "company": "VERIZON WASHINGTON DC, INC.",
13      "ocn": "9211",
14      "ocn_category": null
15    },
16  ...

A structured answer, not a page of text

The data object has 15 named fields. Every response also lists the sources behind the result, the credits charged and whether it was served from your cache.

Fields returned in data by Carrier Lookup (original carrier)
Field Type
phone_e164 string
npa_nxx_block object
original_carrier object
rate_center string or null
state string
And 10 more fields in the API reference.
Named fields. Porting is not reflected (ported: unknown), so a number moved to another carrier still shows its original one. NANPA data has no carrier category, so line type is only a hint from the carrier name. Canada and the Caribbean are not covered.
1. Your requestone API key
2. Your cache7 daysRepeat: 0 credits
3. Data sourcefirst lookupFound: 1 credit
4. ResultJSON
A repeat lookup is free. Results are cached per account for 7 days. Ask the same question again inside that window and the response comes back with cache_hit: true and no charge.
Terminal
```
# Sent with every request, for every product
Authorization: Bearer $LOOKVALID_API_KEY
```
One key for your code and your agents. Send your API key as a Bearer token. The same key and the same credit balance cover every other LookValid product. AI agents can call it as a tool on the MCP server at https://YOUR_API_HOST/v1/mcp.

Fields returned in data by Carrier Lookup (original carrier)
Field	Type
phone_e164	string
npa_nxx_block	object
original_carrier	object
rate_center	string or null
state	string

named fields in every answer

days a repeat lookup is free

lookups on the same key and balance

Latest from the changelog

All changes

Priced in credits

Every LookValid product draws on one shared balance. Carrier Lookup (original carrier) uses 1 credit per lookup (numbers outside the covered numbering plan areas are free).

See pricing Get API key

Cost

1credit

Per lookup (numbers outside the covered numbering plan areas are free)

Found1 credit
Nothing found0 credits
Repeat inside 7 days0 credits
Errors and invalid requests0 credits

Questions about Carrier Lookup

01How much does Carrier Lookup (original carrier) cost?

1 credit per lookup (numbers outside the covered numbering plan areas are free). Credits come out of the one balance shared by every LookValid product.

02Am I charged when nothing is found?

No. When the lookup runs and finds nothing, it returns found: false and costs 0 credits. An error costs nothing either.

03How long are results cached?

For 7 days, per account. Repeating the same lookup inside that window returns cache_hit: true and costs 0 credits.

04Which API key do I use?

The same key as every other product. Send it as a Bearer token in the Authorization header. Email hello@lookvalid.com and we set up your account and send the key.

Carrier Lookup

Create a key

Send the request

Read the answer

Priced in credits

Questions about Carrier Lookup

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