# Spaw vs Companies House API: business verification API comparison

How Spaw and Companies House API compare on pricing, billing rules, the registers behind each answer and limits, from Companies House API's public pages checked on 2026-09-10. Corrections: support@spaw.co.

| | Spaw | Companies House API |
| --- | --- | --- |
| Pricing model | Pay-as-you-go credit packs, or optional monthly plans that deposit the same credits every month for less; both through Stripe Checkout, credits from either never expire | No price is published on the developer pages checked; access is through a registered application and its key. |
| Free tier | 10 free credits every month, no card required | not on the pages read |
| Price per 1,000 at about 10k | $7.80 (Growth pack: 5,000 credits for $39), or $5.80 on the Growth monthly plan (5,000 credits for $29 a month) | not on the pages read |
| Price per 1,000 at about 100k | $4.99 (Volume pack: 100,000 credits for $499), or $3.99 on the Volume monthly plan (100,000 credits for $399 a month) | not on the pages read |
| Identifiers no register carried billed | No: an identifier no installed register carries answers unknown_identifier or unsupported_register and costs nothing | not on the pages read |
| Malformed identifiers billed | No: a malformed identifier and a register that has not synced are free too, as are repeats within 7 days | not on the pages read |
| Registers held | Two, synced as bulk files onto the server so no third party sits in the request path: the GLEIF Level 1 golden copy of Legal Entity Identifiers, refreshed daily by its publisher, and the Companies House free company data product for the United Kingdom, republished monthly. Every answer carries the date of the copy it read. | One, and the authoritative one: the UK register itself, answered live rather than from a copy. |
| Jurisdiction coverage | A LEI is global by construction; company numbers are GB only today, because a company number is unique only inside its own register. Anything else answers unsupported_register, free. | The United Kingdom. |
| Cross-register comparison | Yes: where a LEI record names a Companies House number and both files are installed, the legal name and the status are compared and both sides are quoted in agreements, with flags for a disagreement or for a company the national register records as dissolved. | None: it is a single register, so reconciling it with another is the caller's work. |
| Registered address returned | No, deliberately: a registered address is very often somebody's home. The response carries country and jurisdiction, which are enough to answer whether the entity is real and live. | not on the pages read |
| Bulk limit | None: there is no bulk upload for this product, because nobody types a company number into a signup form | not on the pages read |
| Batch API | 500 identifiers per synchronous request | not on the pages read |
| Rate limit | 50 requests per second per key on the business endpoints | "You can make up to 600 requests within a five-minute period"; every further request in that window answers 429 Too Many Requests. |
| Official SDKs | Python, Node.js, PHP | not on the pages read |
| Data retention | Nothing beyond the credit ledger entry that bills the lookup; a monitored list stores the identifiers you saved and each one's status from its last run, and nothing else. | not on the pages read |

## When Companies House API fits better

Anyone who needs the UK register as it stands right now, and only the UK register. It is the registrar's own service and will always be more current than a copy of its monthly file.

- The data is live: a strike-off, an incorporation or a status change is visible the moment the registrar records it
- It is the register of record, so nothing sits between you and the answer
- 600 requests per five minutes is generous for a lookup workload

## When Spaw fits better

Developers who want to know an identifier belongs to a real, live entity, and want the LEI record and the national register checked against each other rather than trusted separately.

- Companies House answers live; Spaw answers from the free company data product, republished monthly within five working days of the month end, so a Spaw answer can be up to five weeks behind, and every answer carries the date of the copy
- Spaw reads Legal Entity Identifiers as well, against the GLEIF golden copy, and compares the two records where a LEI names a UK company number
- Spaw's identifiers are one endpoint, one key and one balance with its other five signals
- Spaw returns no registered address and holds no register of where people live: it carries country and jurisdiction, which answer whether the entity is real and live

## Questions

**Does Spaw charge for identifiers it cannot find?** No. A lookup costs 1 credit only when a register answers. A malformed identifier, one no register carries, an identifier from a register this server does not hold, and a register that has not synced are all free, because none of them told you anything you could not have worked out. A repeat of the same identifier within seven days is free too. Companies House API does not publish how it bills them.

**Can I check a list of identifiers?** In batches, and on a schedule. There is deliberately no bulk upload for this product: POST /v1/entity/batch takes 500 identifiers a call under the single-lookup billing rules, and a monitored list keeps up to 500 identifiers under a weekly or monthly re-check that emails you when one leaves a register, is recorded as dissolved, or stops agreeing with the other register.

**Is there a free tier?** Every Spaw account receives 10 free credits at the start of each month with no card on file, and unused credits accumulate. Companies House API does not publish a free tier on the pages checked.

## Sources (checked 2026-09-10)

- [Companies House developer hub](https://developer.company-information.service.gov.uk/)
- [Companies House API rate limiting](https://developer-specs.company-information.service.gov.uk/guides/rateLimiting)

Companies House API is a trademark of its owner. Spaw is not affiliated with it.

Reference: https://spaw.co/compare/companies-house-api