Twilio phone and email validation

Check line type before you send SMS or place calls through Twilio, at a lower per-lookup cost than Twilio Lookup.

Why validate inside Twilio

Every SMS to a landline through Twilio is a wasted segment, and every A2P message to an invalid number counts against your error rate. Calling LookupLab before the Messages API filters both out. Twilio Lookup does the same thing, at a higher per-query price and without email or IP in the same key.

The pattern is one function: validate, then send only if line_type is mobile.

Setup

In your send function, call GET https://lookuplab.io/api/v1/phone/?number=... first.
If data.valid is false, skip and log. If data.line_type is landline, skip SMS and queue a call instead.
Send through Twilio with the normalized data.number in E.164.
Cache results for seven days on your side if you message the same numbers repeatedly.

What teams build with it

Cut SMS spend on landlines to zero.
Keep A2P 10DLC error rates low.
Normalize numbers to E.164 before sending.

Get a key and connect Twilio

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 docs

Questions

Why not just use Twilio Lookup?

You can. LookupLab is cheaper per query, bills only successful lookups, and adds email and IP under the same key. See the comparison page.

Related: Telnyx