# Postio, free: Phone validation API

> Postio phone validation parses and formats a number, then runs a live HLR carrier lookup — so you learn not just whether a number is well-formed but which carrier holds it now, whether it has been ported, and whether it is reachable.

Postio's phone validation API on its 100 free lookups plan. It costs $0.00 per 1,000 phones. It returns 7 of the 9 key fields we check: Number, Formats, Validity, Type, Carrier, Porting and roaming, Place.
We haven't run Postio through [our phone validation API benchmark](https://datacircle.dev/best-phone-validation-api.txt) yet.
This plan is free. We rank 888 plans for phone validation APIs by price. Half the plans cost $3.376 per 1,000 phones or less.
[Botoi's $199 monthly plan](https://datacircle.dev/validate-phone-apis/botoi/199-monthly/llms.txt) is the cheapest paid plan per 1,000 phones: as little as $0.0066. Botoi's $199 monthly plan covers up to 1,000,000 phones a day.
[Data247](https://datacircle.dev/validate-phone-apis/data247/12-pack-membership-get-v3-0-verify247-phone/llms.txt), [Foxentry](https://datacircle.dev/validate-phone-apis/foxentry/top-up-pay-as-you-go-post-phone-validate-validate-phone-number-extended/llms.txt) and [HLR Lookups](https://datacircle.dev/validate-phone-apis/hlr-lookups/top-up-1-1m-post-hlr-lookup/llms.txt) are the best phone validation API providers in the Datacircle benchmark.

- This page: https://datacircle.dev/validate-phone-apis/postio/free
- [Phone validation API: 40+ providers compared](https://datacircle.dev/best-phone-validation-api.txt)
- Get it: https://postio.co.uk/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- Request: `GET https://api.postio.co.uk/v1/phone/{number}`
- API key: with the plan, on https://postio.co.uk/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- Its API docs: https://postio.co.uk/docs/phone?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- Sold by: Postio (https://postio.co.uk?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing)
- Checked: 2026-11-03

## In the answer

- Completeness: 78%
- Number: ✓
- Formats: ✓
- Validity: ✓
- Type: ✓
- Carrier: ✓
- Porting and roaming: ✓
- Place: ✓

## Price

- $ per 1,000 phones: $0.00
- Per: call
- Billing: free

## Aggregators

- Aggregators: none

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: Postio phone validation parses and formats a number, then runs a live HLR carrier lookup — so you learn not just whether a number is well-formed but which carrier holds it now, whether it has been ported, and whether it is reachable.

## Data

- Freshness: live
- Countries: Worldwide
- What it checks: numbering plan, carrier, line in service
- Keep data: no limit
- Use data: Don't use the API for fraud, spam targeting, stalking, harassment, or anything that breaks UK law. Because the address service uses Royal Mail PAF data, you must also keep to the PAF End User Terms — in particular, don't copy, extract, resell, republish or publicly display PAF data except as those terms allow, don't use it to build a competing product, and don't try to reverse-engineer the underlying data files. Don't use automated means to scrape or bulk-harvest responses beyond your purchased lookups.

## Plan

- Pay: $0
- You get: 100 requests
- Enough for: 100 calls

## Rate limit

- Per second: 30
- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: number
- Method: GET
- Path: /phone/{number}

## About the plan

- Plan: 100 free lookups
- Who can get it: anyone

## The 22 fields the plan's answer can hold

success, number, valid number, possible number, line type, country code, country name, national format number, international format number, E.164 number, original carrier, current carrier, ported, reachable, MCC, MNC, lookup level, lookup error, result count, request ID, worker time, lookup time

## Postio's plans (2)

- [Postio, free](https://datacircle.dev/validate-phone-apis/postio/free/llms.txt): $0.00 per 1,000, 78% complete, live
- [Postio, top-up from £10](https://datacircle.dev/validate-phone-apis/postio/top-up-from-10/llms.txt): $13.335 per 1,000, 78% complete, live

## Postio's calls for this API (1)

- `GET /phone/{number}`: [Postio, free](https://datacircle.dev/validate-phone-apis/postio/free/llms.txt)

## Postio's APIs (2)

- [Postio: email verification API pricing, 2 plans](https://datacircle.dev/validate-email-apis/postio/free/llms.txt)
- [Postio: phone validation API pricing, 2 plans](https://datacircle.dev/validate-phone-apis/postio/free/llms.txt)

## Postio: phone validation API alternatives

- [1Lookup, $7,990 yearly, Professional (annual), POST /bulk/jobs, Create a bulk job (type hlr_lookup)](https://datacircle.dev/validate-phone-apis/1lookup/7990-yearly-professional-annual-post-bulk-jobs-create-a-bulk-job-type-hlr-lookup/llms.txt): $13.317 per 1,000, 67% complete, live
- [HLR Lookup, £2,500 pack, 1,000,000 lookups, POST /batches/{id}/sourcejson, Bulk uploads via API, full](https://datacircle.dev/validate-phone-apis/hlr-lookup/2500-pack-1000000-lookups-post-batches-id-sourcejson-bulk-uploads-via-api-full/llms.txt): $13.335 per 1,000, 89% complete, live
- [PhoneVerify, top-up, Volume 10k-50k numbers](https://datacircle.dev/validate-phone-apis/phoneverify/top-up-volume-10k-50k-numbers/llms.txt): $13.335 per 1,000, 33% complete, live
- [Listar, top-up from €100,000, Diamond, POST /search/verify-whatsapp](https://datacircle.dev/validate-phone-apis/listar/top-up-from-100000-diamond-post-search-verify-whatsapp/llms.txt): $13.504 per 1,000, 22% complete, live

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-11-03.

- https://postio.co.uk?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://postio.co.uk/docs/errors?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://postio.co.uk/docs/faq?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://postio.co.uk/docs/phone?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://postio.co.uk/docs/reference?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://postio.co.uk/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://postio.co.uk/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://postio.co.uk/terms?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing