Carrier lookup · HTTPS API
Do you know which carrier actually serves a number — and whether it can receive a text — before you send? A phone carrier lookup API should return the current provider, the line type (mobile, landline, or VoIP), and a location that does not rely only on the area code. SubscriberVerify's HTTPS lookup API does that in one request, so you can route, time, and filter a number before it hits a dialer or SMS queue.
Try it with 10,000 free lookups—no credit card required. It may take up to 2 business days for a trial link. Or create an account with 100,000 lookups for $50.
What the API returns
Authenticate with your API key and send a 10-digit US number. The fields below come from the API documentation. Optional flags can add landline SMS eligibility, litigator screening, or a DNC check (DNC after it is enabled on the account).
| Field | What it tells you |
|---|---|
dipCarrier |
Current carrier name from a live DIP lookup. |
dipCarrierType / nanpType |
Line type such as mobile or landline. dipCarrierType is the live DIP type; nanpType is the phone type per NANP records. |
dipCarrierSubType |
Finer class such as PCS or CLEC. See carrier subtypes explained. |
nanpCarrier |
Carrier per NANP records. The docs note this is not authoritative due to porting — prefer dipCarrier. |
dipPorted |
Whether the number looks ported, with dipLrn and dipOcn when present. |
smsEligible / deliverable |
smsEligible is the primary send/no-send signal; it is present only when true. deliverable means the number appears eligible to receive texts. Carriers do not guarantee delivery. |
action |
Recommended list action: send, unsubscribe, blacklist, or error. |
geoState, geoCity, timezone |
Estimated location and time zone. geoSource is ip or area-code, so you can see which method was used. |
deactivationDate |
Most recent deactivation date when we have one. Recent deactivation notices are included with the lookup. |
| Optional checks | landlinesmslookup=1 adds landline SMS eligibility (1 extra credit on landline records). litigatorfilter=1 adds litigator fields. dnccheck=1 adds DNC fields after DNC is enabled on the account. See DNC screening and LitigatorVerify. |
Verified from our docs
This pair is copied from the public API documentation
(DIP + landline SMS eligibility example). Replace YOUR_API_KEY with the key from your dashboard.
The phone number is the example used in the docs, not a live lookup. Form POST and JSON POST are also accepted; those request bodies are in the docs.
Request (HTTPS GET)
https://api2.subscriberverify.com/api?key=YOUR_API_KEY&phone=8015550100&landlinesmslookup=1Example response
{
"subscriber": "8015550100",
"action": "send",
"deliverable": "true",
"smsEligible": "true",
"nanpType": "mobile",
"dip": "success",
"dipCarrier": "Verizon",
"dipCarrierType": "mobile",
"dipMessagingLookup": "true",
"dipMessagingEnabled": "true",
"dipMessagingProvider": "Example Messaging Provider",
"geoState": "UT",
"geoSource": "area-code",
"timezone": "America/Denver"
}
This example did not include an ip, so geoSource is area-code.
The standard lookup in the docs adds ip (the opt-in address) to improve geolocation.
SubscriberVerify's location algorithm doesn't rely only on the area code. It can use other data, such as the opt-in IP address, and the response tells you which source it used.
Where teams use it
A carrier lookup is not a legal opinion, and a clean result is not permission to contact someone. It answers practical questions before a call or text goes out.
Federal telephone solicitations are generally limited to 8 a.m. to 9 p.m. in the recipient's local time, and several states are stricter. Time zone and location fields help you schedule inside that window. In many jurisdictions, TCPA violations can cost $500 to $1,500 each. Pair this lookup with DNC screening and a litigator check when your program needs them. This is general information, not legal advice.
Texting a landline or a deactivated number wastes carrier fees and can hurt delivery. Line type, smsEligible, and deactivation data help you keep those numbers off a campaign. For landlines that might still take texts, add landlinesmslookup=1 (one extra credit on landline records).
A number that was just deactivated, recently ported, or tied to a known TCPA litigator is a poor one to dial or text. Deactivation notices are included. Add litigatorfilter=1 when you want litigator flags in the same response. See LitigatorVerify for that workflow.
API or a list
Call the lookup API at lead capture, in a dialer, or from a CRM. For a campaign file, use the bulk phone validator (CSV upload) or the bulk API, which accepts up to 1,000 numbers per request.
HTTPS GET or POST to https://api2.subscriberverify.com/api with your key and a phone number. Full field list and more examples are in the API documentation.
Upload a list and get carrier, line type, location, and optional DNC or litigator flags back in one file. Details are on the bulk phone validator page.
Pricing and trial
The free trial includes 10,000 lookups and does not require a credit card. It may take up to 2 business days for our team to send a trial link.
When you are ready to scale, create an account with 100,000 lookups for $50, by API, CSV upload, or both.
Carrier lookup and SMS eligibility (DIP) use 1 credit and are included. Estimated time zone and recent deactivation notices do not add a credit.
Landline SMS eligibility adds 1 credit on landline records. Litigator screening adds 1 credit when you set litigatorfilter=1.
A DNC check adds 1 credit when you set dnccheck=1, after DNC is enabled on the account. The API documentation lists the credit cost of each option.
Ready to look up
Start with 10,000 free lookups, or create an account with 100,000 lookups for $50 and call the API the same day you get a key.
