A KYB (Know Your Business) API is a REST interface that checks a company against official data: it confirms the company exists on its register, reads its status and officers, and screens it for insolvency and sanctions, so a fintech, marketplace or bank can automate business onboarding instead of checking by hand. The checks and the call behind each are in the table above.

What data does a KYB API return?

For this one: the register record (legal name, legal form, status, registered address, founding date), directors where the register publishes them, UK beneficial owners from the PSC register, corporate insolvency notices in sixteen markets, and sanctions screening results (beta). Scope limits by country are in the coverage table.

Is there a free KYB API?

Starter begins with a 14-day trial of 500 credits with a card required and nothing charged for 14 days: company search, company records and insolvency checks in every live country, and up to 25 calls a month each to try sanctions screening (single names), people and company events. Batch sanctions screening needs Professional, 29.99 euros a month for 10,000 credits.

Does the KYB API return beneficial owners (UBO)?

For United Kingdom companies, yes: the persons and companies with significant control from the PSC register, as appointments with is_beneficial_owner set to true. Other countries return no beneficial-ownership data; national UBO registers such as Spain's RBR or France's RBE are not queried.

Is the sanctions screening production-ready?

It is in beta. It screens names against the official lists as at November 2026 (the EU, UN, OFAC and UK lists, Australia (DFAT), the French asset-freeze register and the US Consolidated Screening List) with a tunable threshold, and a clear result means no hit at or above the threshold on the active lists, not a certification. PEP screening is beta, Spain only, with no relatives or close associates.

Is this a KYB API or a KYB platform?

It is the data layer of a KYB process, not a KYB platform. A platform adds workflows, case management and identity checks; this API returns official register records, status, directors where published, insolvency notices and sanctions screening (beta) as JSON for you to build into your own onboarding. It does not verify people: no KYC, no liveness, no adverse media.

Can I keep a company monitored after onboarding?

Yes. POST /monitor subscribes the company and posts a signed webhook on a status change, a dissolution, a new sanctions match (beta) or a register-change event, in every live country except France and Chile. Every plan gets webhooks: Starter monitors 25 companies, Professional 250 and Scale 2,500. Filed annual accounts are on the Scale plan.

Is this a KYC API for individuals?

No. It verifies companies from their official registers and screens names. It does not verify the identity of people: no identity documents, no liveness checks and no adverse-media screening.

KYB API for developers: verify a company from its registry number

Name: Prometiam KYB API
Price: 9.99 EUR

One request turns a company number and a country into the official register record. This is the call, and the answer, in full.

curl "https://api.prometiam.com/functions/v1/risk-api/companies/search?country=GB&company_number=00445790&limit=1" -H "Authorization: Bearer $PROMETIAM_API_KEY"

{
  "data": [{
    "id": 2000004984338,
    "country": "GB",
    "company_number": "00445790",
    "company_name": "TESCO PLC",
    "legal_form": "PLC",
    "status": "active",
    "stage": "active",
    "founding_date": "1947-11-27",
    "address": "TESCO HOUSE, SHIRE PARK, KESTREL WAY, WELWYN GARDEN CITY, AL7 1GA, UNITED KINGDOM",
    "lei": "2138002P5RNKC5W2JZ46",
    "nace_class": "47.11",
    "register": "Companies House"
  }],
  "pagination": { "count": 1, "has_more": false, "next_cursor": null }
}

Plans: Starter EUR 9.99 a month (1,000 credits), Professional EUR 29.99 (10,000), Scale EUR 99.99 (50,000).

A KYB API is a REST API that checks a business counterparty against official sources, so onboarding can be automated. This KYB API is a Know Your Business API for 37 company registers: Spain, France, the United Kingdom, Ireland, Poland, Norway, Finland, Sweden, Belgium, Croatia, Denmark, Estonia, Slovakia, Switzerland, Latvia, Cyprus, Romania, Lithuania, Canada, Australia, Japan, Israel, Singapore, Colombia, Taiwan, Czech Republic, Germany, Argentina, Ukraine, Serbia, Slovenia, Ecuador, Chile, Mexico, the Netherlands, Brazil and, in the United States, the New York, Colorado, Connecticut, Pennsylvania, Florida, Iowa, the District of Columbia, Texas and Oregon registers, the Massachusetts public-record extract of the Corporations Division, plus SEC filers and LEI holders from other states. Send a company number and a country and get the record back: legal name, status and registered address, the directors and, for the United Kingdom, the beneficial owners where the register publishes them. Corporate insolvency notices in sixteen markets and sanctions screening (beta) complete the check. One key, one response shape, published prices, no sales call.

Most teams start smaller: looking up or validating a company at sign-up, invoicing or CRM entry is a single call (about 1 credit, about EUR 0.01) on the same key, see the company lookup API.

What a KYB check needs, and which call answers it

Is the company on the register? GET /companies/search with company_number and country.
Is it still trading? The stage and status fields of the same record.
Who runs it? GET /companies/{id}: appointments, for Spain, France, the United Kingdom, Norway, Poland and the Czech Republic (Polish natural persons are masked by the register itself; Czech natural persons are the name and the month and year of birth only).
Who owns it? Appointments with is_beneficial_owner, from the UK register of persons with significant control.
Is it in an insolvency proceeding? POST /insolvency/check, corporate notices in sixteen markets.
Is it heading for a strike-off? include=risk_flags returns the registry-compliance signal for Spain, the United Kingdom, Ireland and Norway.
Are the company or its people sanctioned? POST /sanctions/screen (beta), up to 50 names a call.
Has anything changed since onboarding? POST /monitor, webhook alerts for every live country except France and Chile.

KYB control map and evidence file

Each control in a KYB policy (entity identity, directors, beneficial owners, sanctions, PEP, insolvency, ongoing monitoring, record-keeping) maps to a call, its credits and the field that evidences it; adverse media and identity checks of people are not offered. See the KYB control map and evidence file. Informational, not legal advice.

Beyond onboarding: monitoring, filed accounts, insolvency

After onboarding, add the company to monitoring and get a signed webhook on a status change, a dissolution, a sanctions match (beta) or a register-change event (on every plan: 25 monitored companies on Starter, 250 on Professional, 2,500 on Scale; every live country except France and Chile): see the company monitoring API. Filed annual accounts are on the Scale plan (EUR 99.99 a month; other plans get 10 calls a month): GB, FR, DK, SE, NO, LV, FI (digitally filed), EE, LT and RO headline figures, CO (Supersociedades filers), US SEC filers and listed companies in ES, PL, HR, BE and BR, plus tax records for FI and AU. Corporate insolvency notices in sixteen markets have their own insolvency API, and a batch call checks up to 100 companies at once.

A KYB check in four calls

curl "https://api.prometiam.com/functions/v1/risk-api/companies/search?company_number=00519500&country=GB&limit=1" -H "Authorization: Bearer $PROMETIAM_API_KEY"

Then GET /companies/{id}?country=GB&include=risk_flags for the status, officers and owners, POST /insolvency/check for insolvency notices, and POST /sanctions/screen with the company, its owners and its directors. A full check is about 22 credits.

Coverage by country

Every country returns the register record and status, and sanctions screening takes any name. Directors: Spain, France, the United Kingdom, Norway, Poland and the Czech Republic (Polish natural persons are masked by the register itself; Czech natural persons are the name and the month and year of birth only). Beneficial owners: the United Kingdom (PSC register). Corporate insolvency notices: France, the United Kingdom, Norway, Finland, Sweden, Croatia, Denmark, Switzerland (where the notice names the debtor's UID), Spain, Latvia, Estonia and Singapore among the registry countries, plus Germany, Austria and the United States without a company record, and the Netherlands, where a notice links only to an entity that holds an LEI; Belgium shows a bankruptcy in the company status. Strike-off warning: Spain, the United Kingdom, Ireland and Norway. Monitoring: every live country except France and Chile. Ireland is company-level, with no officers. Sole traders are never served in Sweden, Belgium, Croatia and Denmark.

What this API does not do

It does not verify the identity of people (no documents, no liveness), it has no adverse-media screening, its PEP screening is beta and Spain only with no relatives or close associates, and beneficial owners come only from the UK PSC register. Sanctions screening is beta: a clear result is not a certification. The API supplies the evidence; the decision stays with your compliance process.

Price

Starter begins with a 14-day trial of 500 credits with a card required and nothing charged for 14 days: the search, the record and the insolvency check in full, and 25 single-name sanctions screening calls a month. Starter is EUR 9.99 a month for 1,000 credits, without screening (sanctions watchlists only). Professional is EUR 29.99 for 10,000 credits with full sanctions screening, and Scale EUR 99.99 for 50,000. At about 22 credits a check (1 for the search, 1 for the record, 2 for the insolvency check and 3 for each of six names screened), Professional covers about 450 checks a month.

To price your own volume, use the credit estimator on the pricing page.

KYB onboarding tutorial · KYB and sanctions for fintech · What is KYB? · EU and UK KYB APIs compared · Company lookup API · Company monitoring API · Insolvency API · MCP server · Pricing · Trust and security

In other languages: API KYB (français) · API KYB (español)

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What a check costs

Plan	Price	Credits a month	Checks a month at ~22 credits
Starter trial (14 days)	€0, card required, nothing charged for 14 days	500 in total	Steps 1 to 3 in full; step 4 one name at a time, 25 screening calls a month
Starter	€9.99 a month	1,000	About 250 checks of steps 1 to 3 (4 credits each); no screening, sanctions watchlists only
Professional	€29.99 a month	10,000	About 450, with full sanctions screening
Scale	€99.99 a month	50,000	About 2,200

Frequently asked questions

What is a KYB API?: A KYB (Know Your Business) API is a REST interface that checks a company against official data: it confirms the company exists on its register, reads its status and officers, and screens it for insolvency and sanctions, so a fintech, marketplace or bank can automate business onboarding instead of checking by hand. The checks and the call behind each are in the table above.
What data does a KYB API return?: For this one: the register record (legal name, legal form, status, registered address, founding date), directors where the register publishes them, UK beneficial owners from the PSC register, corporate insolvency notices in sixteen markets, and sanctions screening results (beta). Scope limits by country are in the coverage table.
Is there a free KYB API?: Starter begins with a 14-day trial of 500 credits with a card required and nothing charged for 14 days: company search, company records and insolvency checks in every live country, and up to 25 calls a month each to try sanctions screening (single names), people and company events. Batch sanctions screening needs Professional, 29.99 euros a month for 10,000 credits.
Which countries does the KYB API cover?: Company records for Spain, France, the United Kingdom, Ireland, Poland, Norway, Finland, Sweden, Belgium, Croatia, Denmark, Estonia, Slovakia, Switzerland, Latvia, Cyprus, Romania, Lithuania, Canada, Australia, Japan, Israel, Singapore, Colombia, Taiwan, Czech Republic, Germany, Argentina, Ukraine, Serbia, Slovenia, Ecuador, Chile, Mexico, the Netherlands, Brazil and the United States. Directors for Spain, France, the United Kingdom, Norway, Poland and the Czech Republic (Polish natural persons are masked by the register itself; Czech natural persons are the name and the month and year of birth only); beneficial owners for the United Kingdom. Corporate insolvency notices in sixteen markets: France, Germany, the United Kingdom, Austria, Switzerland, Norway, Finland, the United States, the Netherlands, Denmark, Croatia, Sweden, Spain, Latvia, Estonia and Singapore. Sanctions screening (beta) takes any name.
Does the KYB API return beneficial owners (UBO)?: For United Kingdom companies, yes: the persons and companies with significant control from the PSC register, as appointments with is_beneficial_owner set to true. Other countries return no beneficial-ownership data; national UBO registers such as Spain's RBR or France's RBE are not queried.
Is the sanctions screening production-ready?: It is in beta. It screens names against the official lists as at November 2026 (the EU, UN, OFAC and UK lists, Australia (DFAT), the French asset-freeze register and the US Consolidated Screening List) with a tunable threshold, and a clear result means no hit at or above the threshold on the active lists, not a certification. PEP screening is beta, Spain only, with no relatives or close associates.
What does a KYB check cost?: Every successful call costs credits, each batch item is charged on its own and errors are free. The four-step check on this page is about 22 credits: 1 for the search, 1 for the record, 2 for the insolvency check and 3 for each of six names screened. Professional, 29.99 euros a month for 10,000 credits, covers about 450 such checks a month, about 7 euro cents each; Scale, 99.99 euros for 50,000 credits, about 2,200 checks, about 4 euro cents each.
Is this a KYB API or a KYB platform?: It is the data layer of a KYB process, not a KYB platform. A platform adds workflows, case management and identity checks; this API returns official register records, status, directors where published, insolvency notices and sanctions screening (beta) as JSON for you to build into your own onboarding. It does not verify people: no KYC, no liveness, no adverse media.
Can I keep a company monitored after onboarding?: Yes. POST /monitor subscribes the company and posts a signed webhook on a status change, a dissolution, a new sanctions match (beta) or a register-change event, in every live country except France and Chile. Every plan gets webhooks: Starter monitors 25 companies, Professional 250 and Scale 2,500. Filed annual accounts are on the Scale plan.
Is this a KYC API for individuals?: No. It verifies companies from their official registers and screens names. It does not verify the identity of people: no identity documents, no liveness checks and no adverse-media screening.