Free Company Information API: Choose by Coverage, Fields, and Access

Define what “company information” means for your application

Start with Companies House when you need public UK company-register information. Start with SEC data APIs when you need an EDGAR filer's submissions or financial disclosures. Both are useful public-data starting points, with different populations and outputs. Companies House public data · SEC data APIs

For international company records, evaluate OpenCorporates against its access and licensing conditions. For a downloadable company dataset, consider People Data Labs' free dataset. A recurring domain-enrichment workflow may still need a paid service.

This comparison is based on official documentation checked on September 29, 2026. It distinguishes public API access, conditional free access, a dataset download, and paid enrichment. We did not run a cross-provider coverage or accuracy test.

A free company information API can serve several different tasks. Choose the task before comparing the providers.

Searches for free company data often mix these tasks. A free company search API may return a set of candidates; your application still has to resolve which one matches the account.

Define the required geography and fields as well. A UK registration-status lookup and a global employee-size lookup should use different evaluation criteria. For help defining the attributes, see the firmographic data guide.

Compare the available access models

Companies House for UK company-register information

Companies House makes public company data available through its API without a data-access charge. Its developer documentation requires authentication and describes a limit of 600 requests within a five-minute period. Requests above the limit receive HTTP 429 responses for the remaining window. Free public data · Getting started · Rate limits

Choose this route when the required answer is grounded in the company register. Identify the relevant company record, then check the resources and fields needed by your application. Avoid assuming that registration data contains the marketing or workforce attributes used in a sales-enrichment product.

SEC data APIs for filers and disclosures

The SEC documents public JSON APIs for submissions history and XBRL data. They use a company's CIK and require no authentication or API key. The service also documents that data.sec.gov does not support CORS, which matters when designing a browser-based application. SEC API documentation

Choose the SEC route when your application begins with an EDGAR filer or a supported disclosure task. Keep the filer population explicit in the product requirements. A missing private business should not automatically be counted as an API failure.

OpenCorporates for company-identity research

OpenCorporates documents company search and legal-entity records. Its API requires a key. Free access is stated for open-data projects under its open-license conditions, with usage limits dependent on the account and plan. A commercial integration needs an access arrangement appropriate to its use. OpenCorporates API reference

This is worth evaluating when jurisdiction and company identity are central to the task. Record the jurisdiction and company number together; a name alone can identify several different businesses.

PDL's free dataset for a local index

People Data Labs documents a free downloadable company dataset with attributes including name, website, industry, size, and location. Its documentation states a quarterly update schedule and a selection requirement of at least one current associated employee in PDL data. Free Company Dataset

Evaluate it when a periodically refreshed local index can serve the task. Account for downloading, storage, indexing, matching, and refresh work. The free dataset does not establish that PDL's enrichment or search API is available without charge.

Glasser for paid company-data operations

Glasser's official use-case catalog includes company search and company enrichment. Its operating model documents endpoint discovery, contract inspection, and paid execution. Compare this route when you need company data inside an agent workflow and the public or downloadable options do not supply the required operation. Glasser use cases · Operating model

The direct-access providers listed above are evaluated separately. This article does not imply that every listed service is available through Glasser.

Test coverage before building around an endpoint

Prepare a small set of representative companies with known identity evidence. Include at least one ambiguous name, a subsidiary, and a company outside your main geography. Keep the evaluation manageable enough to inspect the results manually.

For each option, record:

1. Population fit: Is this company expected to exist in the source's covered population?
2. Input fit: Do you have the identifier or search input the service requires?
3. Identity result: Does the returned entity match the company you meant?
4. Required fields: Are the specific fields available and interpretable?
5. Freshness evidence: What does the available timestamp actually describe?
6. Access conditions: Can your intended application use the documented access model?

Record each evaluation criterion separately so a correct company match does not obscure missing fields or access restrictions.

For example, a company-name search could find both a parent and a local subsidiary. Check the jurisdiction, address, identifiers, and relationship evidence before accepting the match. A successful response only confirms that the service processed the request; your application still needs an identity decision.

Preserve the meaning of missing and conflicting fields

A shared application schema is useful, but it should not flatten meaningful differences between sources.

Keep registered_address separate from headquarters_location. Preserve incorporation date separately from a reported founding year. Distinguish a published employee range from a calculated employee count. Store the source and available observation date alongside the value.

Use an explicit status for every required field: available, absent in this record, outside the source's scope, or unresolved because the entity match is uncertain. These statuses help you decide whether another source could close the gap.

Consider a fictional workflow that requires a company's headquarters country and employee range. A registry returns a matching legal entity with a registered address but no employee field. The record may be perfectly useful for legal-entity identification while still failing the workflow's two-field requirement. Preserve that partial contribution when evaluating a second source.

When sources disagree, inspect definitions and entity scope before choosing the newest retrieval. A recently downloaded record may contain an older underlying observation. Keep both values if the conflict cannot yet be resolved.

Budget the integration beyond the request price

Free access can be economical when the source matches the task. Estimate the work around that access before choosing an architecture.

For a registry API, include entity matching, authentication handling, throttling, and exception review. For a downloaded dataset, include storage, index construction, refresh jobs, and any source-appropriate use conditions. For a paid enrichment route, include the contracted data charges and the work required to validate the returned company.

Use a simple planning model:

Monthly operating cost = data access + infrastructure + maintenance + review
Cost per accepted company = operating cost / companies meeting the requirement

As an illustrative example, a free data source requiring three hours of monthly maintenance at an internal planning rate of $50 per hour has $150 of maintenance cost before infrastructure or review. A paid alternative should be evaluated using its own full costs; payment alone does not remove matching or quality work.

Do not count every retrieved record as accepted. Define acceptance by the required company identity and fields, then compare the options using that denominator. Keep development costs separate if you want the monthly figure to describe ongoing operation.

Questions about free company information APIs

Is there one free API for every company worldwide?

The sources compared here have different populations, field sets, and access conditions. Choose a primary source for the required task, then evaluate a second source only for the gaps you have actually observed. This research does not establish universal coverage for any option.

Can I enrich a company using only its domain?

Some company-enrichment services accept identity inputs for matching, while registry and filer systems organize records around their own identifiers. Check the chosen endpoint's input contract and evaluate ambiguous domains before building a domain-only workflow. PDL's company-enrichment overview

Does a free dataset replace a company API?

It can serve an application that is designed to host, index, and refresh that dataset. It brings a different operating model from calling a provider for each lookup. Evaluate the update schedule and included fields against the task.

When is paying for company data reasonable?

When the paid operation supplies a required capability or reduces enough operating work to justify its full cost. Measure that value using correctly matched companies with the fields your workflow needs.