# SerwerSMS, free trial, POST /phones/check: Phone validation API

> Enhanced access to the registry through which you can verify current membership and availability of number in network.

SerwerSMS's phone validation API on its Free trial plan. It costs $0.00 per 1,000 phones. It returns 4 of the 9 key fields we check: Number, Validity, Carrier, Porting and roaming.
We haven't run SerwerSMS 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/serwersms/free-trial-post-phones-check
- [Phone validation API: 40+ providers compared](https://datacircle.dev/best-phone-validation-api.txt)
- Get it: https://en.serwersms.pl/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- Request: `POST https://api2.serwersms.pl/phones/check`
- API key: with the plan, on https://en.serwersms.pl/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- Its API docs: https://dev.serwersms.pl/https-api-v2/hlr-zaawansowany-sprawdzanie-dostepnosci-numeru?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- Sold by: SerwerSMS (https://www.serwersms.pl?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing)
- Checked: 2026-11-04

## In the answer

- Completeness: 44%
- Number: ✓
- Validity: ✓
- Carrier: ✓
- Porting and roaming: ✓

## Price

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

## Aggregators

- Aggregators: none

## Charges

- Also pays for: Sending SMS messages with the same content: 100 free messages

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: Enhanced access to the registry through which you can verify current membership and availability of number in network.

## Data

- Freshness: live
- Countries: Worldwide
- What it checks: numbering plan, carrier, line in service
- Keep data: no limit
- Use data: Subscriber shall not be entitled irrespective of the technical means used to enable third parties to use Serwer SMS or to use Serwer SMS for third parties needs in any other way than described in the paragraph 2. [...] It is forbidden to share account to third parties, unless the Account is used by an authorized employee or associate of the Subscriber.

## Plan

- Pay: $0
- Expires: 14 days

## Rate limit

- Batch: 50,000

## Speed

- Answer: in the call or by polling

## The call

- You send: phone. Optional: id, url
- Method: POST
- Path: /phones/check

## About the plan

- Plan: Free trial
- Who can get it: entrepreneurs: its terms define a Subscriber as an entrepreneur

## The 7 fields the plan's answer can hold

phone number, status, IMSI, original network, ported, current network, status description

## SerwerSMS's plans (7)

- [SerwerSMS, free trial, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/free-trial-post-phones-check/llms.txt): $0.00 per 1,000, 44% complete, live
- [SerwerSMS, top-up from PLN 50, Prepaid, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/top-up-from-pln-50-prepaid-post-phones-check/llms.txt): $12.876 per 1,000, 44% complete, live
- [SerwerSMS, PLN 49 monthly, Lite, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/pln-49-monthly-lite-post-phones-check/llms.txt): $12.876 per 1,000, 44% complete, live
- [SerwerSMS, PLN 99 monthly, Standard, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/pln-99-monthly-standard-post-phones-check/llms.txt): $12.876 per 1,000, 44% complete, live
- [SerwerSMS, PLN 199 monthly, Growth, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/pln-199-monthly-growth-post-phones-check/llms.txt): $12.876 per 1,000, 44% complete, live
- [SerwerSMS, PLN 299 monthly, Pro, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/pln-299-monthly-pro-post-phones-check/llms.txt): $12.876 per 1,000, 44% complete, live
- [SerwerSMS, contact us, Individual package, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/contact-us-individual-package-post-phones-check/llms.txt): 44% complete, live

## SerwerSMS's calls (3)

- `POST /phones/check`: [SerwerSMS, free trial, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/free-trial-post-phones-check/llms.txt)
- `POST /phones/lookup`: [SerwerSMS, free trial, POST /phones/lookup](https://datacircle.dev/validate-phone-apis/serwersms/free-trial-post-phones-lookup/llms.txt)
- `POST /phones/nat`: [SerwerSMS, free trial, POST /phones/nat](https://datacircle.dev/validate-phone-apis/serwersms/free-trial-post-phones-nat/llms.txt)

## SerwerSMS's APIs (1)

- [SerwerSMS: phone validation API pricing, 7 plans, POST /phones/check](https://datacircle.dev/validate-phone-apis/serwersms/free-trial-post-phones-check/llms.txt)

## SerwerSMS: phone validation API alternatives

- [ProWebLook, $76.70 yearly, WhatsApp Annual 500, GET /wavalidation](https://datacircle.dev/validate-phone-apis/proweblook/76-70-yearly-whatsapp-annual-500-get-wavalidation/llms.txt): $12.783 per 1,000, 67% complete, live
- [Veriphone, $12.99 monthly, Starter, GET /v3/verify, /v3/verify, full](https://datacircle.dev/validate-phone-apis/veriphone/12-99-monthly-starter-get-v3-verify-v3-verify-full/llms.txt): $12.99 per 1,000, 78% complete, live
- [SignalWire, top-up from $5, Prepaid balance, GET /api/relay/rest/lookup/phone_number/{e164_number}, Look up phone number, full](https://datacircle.dev/validate-phone-apis/signalwire/top-up-from-5-prepaid-balance-get-api-relay-rest-lookup-phone-number-e164-number-look-up-phone-number-full/llms.txt): $13.00 per 1,000, 67% complete, live
- [Verify550, $650 pack, 500,000 Credits, POST /api/bulkPhoneList](https://datacircle.dev/validate-phone-apis/verify550/650-pack-500000-credits-post-api-bulkphonelist/llms.txt): $13.00 per 1,000, 56% 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 2026-11-04.

- https://dev.serwersms.pl/en/https-api-v2/hlr-checking-the-availability-of-the-number?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://dev.serwersms.pl/https-api-v2?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://dev.serwersms.pl/https-api-v2/autoryzacja?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://dev.serwersms.pl/https-api-v2/hlr-zaawansowany-sprawdzanie-dostepnosci-numeru?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://docs.serwersms.pl/SerwerSMS_term_of_use.pdf?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://en.serwersms.pl/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://en.serwersms.pl/services/checking-numbers?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing
- https://serwersms.pl/cennik/cennik-pre-paid?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=phone-validation-api-pricing