fourzerotwo-si

fourzerotwo-si Companies House API

UK Companies House: Every UK company: search, profile, status, registered office, filings, charges and insolvency.

GitHub OpenAPI

Operations 12

GET /v1/companies-house/alphabetical-search UK Companies House: Alphabetical name search #
GET /v1/companies-house/dissolved-search UK Companies House: Dissolved company search #
GET /v1/companies-house/profile UK Companies House: Company profile #
GET /v1/companies-house/registered-office UK Companies House: Registered office #
GET /v1/companies-house/filing-history UK Companies House: Filing history #
GET /v1/companies-house/filing UK Companies House: Filing item #
GET /v1/companies-house/charges UK Companies House: Charges (secured debt) #
GET /v1/companies-house/insolvency UK Companies House: Insolvency #
GET /v1/companies-house/exemptions UK Companies House: Exemptions #
GET /v1/companies-house/uk-establishments UK Companies House: UK establishments #
GET /v1/companies-house/search UK Companies House: Search companies #
GET /v1/companies-house/advanced-search UK Companies House: Advanced company search #

Specifications

⚙
OpenAPI
https://artifacts.apis.io/fourzerotwo-si/openapi/fourzerotwo-si-companies-house-api-openapi.yml

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OpenAPI Specification

fourzerotwo-si-companies-house-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Fourzerotwo Si Companies House API
  version: 1.1.0
  contact:
    url: https://fourzerotwo.si
  description: 'Operations tagged companies-house across 2 of this provider''s published API definitions: openapi.json, fourzerotwo-si-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://fourzerotwo.si
tags:
- name: companies-house
  description: 'UK Companies House: Every UK company: search, profile, status, registered office, filings, charges and insolvency.'
paths:
  /v1/companies-house/alphabetical-search:
    get:
      operationId: companies_house__alphabetical_search
      summary: 'UK Companies House: Alphabetical name search'
      description: 'Companies listed alphabetically around a name — good for name-availability checks. Price: $0.003 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/alphabetical-search
      parameters:
      - name: q
        in: query
        required: true
        description: Name
        schema:
          type: string
        example: Fourzerotwo
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: sample
      x-mcp-tool: companies-house__alphabetical-search
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/dissolved-search:
    get:
      operationId: companies_house__dissolved_search
      summary: 'UK Companies House: Dissolved company search'
      description: 'Search dissolved and removed companies by name. Price: $0.003 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/dissolved-search
      parameters:
      - name: q
        in: query
        required: true
        description: Name
        schema:
          type: string
        example: Woolworths
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: sample
      x-mcp-tool: companies-house__dissolved-search
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/profile:
    get:
      operationId: companies_house__profile
      summary: 'UK Companies House: Company profile'
      description: 'Status, type, incorporation date, SIC codes, accounts and confirmation statement due dates, registered office. Price: $0.005 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/profile
      parameters:
      - name: company_number
        in: query
        required: true
        description: 8-character company number, e.g. "00445790"
        schema:
          type: string
          maxLength: 8
        example: 00445790
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.005000'
      x-free-tier: sample
      x-mcp-tool: companies-house__profile
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/registered-office:
    get:
      operationId: companies_house__registered_office
      summary: 'UK Companies House: Registered office'
      description: 'Current registered office address. Price: $0.002 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/registered-office
      parameters:
      - name: company_number
        in: query
        required: true
        description: 8-character company number, e.g. "00445790"
        schema:
          type: string
          maxLength: 8
        example: 00445790
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.002000'
      x-free-tier: sample
      x-mcp-tool: companies-house__registered-office
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/filing-history:
    get:
      operationId: companies_house__filing_history
      summary: 'UK Companies House: Filing history'
      description: 'Accounts, confirmation statements, appointments and other filings, newest first. Price: $0.005 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/filing-history
      parameters:
      - name: company_number
        in: query
        required: true
        description: 8-character company number, e.g. "00445790"
        schema:
          type: string
          maxLength: 8
        example: 00445790
      - name: category
        in: query
        required: false
        description: accounts, confirmation-statement, officers, capital, mortgage…
        schema:
          type: string
        example: accounts
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.005000'
      x-free-tier: sample
      x-mcp-tool: companies-house__filing-history
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/filing:
    get:
      operationId: companies_house__filing
      summary: 'UK Companies House: Filing item'
      description: 'One filing''s detail and document link. Price: $0.003 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/filing
      parameters:
      - name: company_number
        in: query
        required: true
        description: 8-character company number, e.g. "00445790"
        schema:
          type: string
          maxLength: 8
        example: 00445790
      - name: transaction_id
        in: query
        required: true
        description: Transaction id from filing history
        schema:
          type: string
        example: MzU0MzY3ODg5MGFkaXF6a2N4
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: sample
      x-mcp-tool: companies-house__filing
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/charges:
    get:
      operationId: companies_house__charges
      summary: 'UK Companies House: Charges (secured debt)'
      description: 'Mortgages and charges registered against a company, with lenders and status. Price: $0.008 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/charges
      parameters:
      - name: company_number
        in: query
        required: true
        description: 8-character company number, e.g. "00445790"
        schema:
          type: string
          maxLength: 8
        example: 00445790
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.008000'
      x-free-tier: sample
      x-mcp-tool: companies-house__charges
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/insolvency:
    get:
      operationId: companies_house__insolvency
      summary: 'UK Companies House: Insolvency'
      description: 'Insolvency cases, practitioners and key dates for a company. Price: $0.008 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/insolvency
      parameters:
      - name: company_number
        in: query
        required: true
        description: Company number
        schema:
          type: string
          maxLength: 8
        example: NI017846
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.008000'
      x-free-tier: sample
      x-mcp-tool: companies-house__insolvency
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/exemptions:
    get:
      operationId: companies_house__exemptions
      summary: 'UK Companies House: Exemptions'
      description: 'PSC disclosure exemptions a company holds. Price: $0.002 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/exemptions
      parameters:
      - name: company_number
        in: query
        required: true
        description: Company number
        schema:
          type: string
          maxLength: 8
        example: 00445790
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.002000'
      x-free-tier: sample
      x-mcp-tool: companies-house__exemptions
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/uk-establishments:
    get:
      operationId: companies_house__uk_establishments
      summary: 'UK Companies House: UK establishments'
      description: 'UK branches of an overseas company. Price: $0.002 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/uk-establishments
      parameters:
      - name: company_number
        in: query
        required: true
        description: Overseas company number (FC…)
        schema:
          type: string
          maxLength: 8
        example: FC013958
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.002000'
      x-free-tier: sample
      x-mcp-tool: companies-house__uk-establishments
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/search:
    get:
      operationId: companies_house__search
      summary: 'UK Companies House: Search companies'
      description: 'Find UK companies by name or number, with status, address and incorporation date. Price: $0.003 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/search
      parameters:
      - name: q
        in: query
        required: true
        description: Company name or number
        schema:
          type: string
        example: Tesco
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: sample
      x-mcp-tool: companies-house__search
    servers:
    - url: https://fourzerotwo.si
  /v1/companies-house/advanced-search:
    get:
      operationId: companies_house__advanced_search
      summary: 'UK Companies House: Advanced company search'
      description: 'Filter companies by name, status, SIC code, location and incorporation dates. Price: $0.005 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - companies-house
      externalDocs:
        url: https://fourzerotwo.si/apis/companies-house/advanced-search
      parameters:
      - name: company_name_includes
        in: query
        required: false
        description: Name contains
        schema:
          type: string
        example: bakery
      - name: company_status
        in: query
        required: false
        description: active, dissolved, liquidation…
        schema:
          type: string
        example: active
      - name: sic_codes
        in: query
        required: false
        description: SIC code
        schema:
          type: string
      - name: location
        in: query
        required: false
        description: Town, county or postcode area
        schema:
          type: string
        example: Kent
      - name: incorporated_from
        in: query
        required: false
        description: YYYY-MM-DD
        schema:
          type: string
      - name: incorporated_to
        in: query
        required: false
        description: YYYY-MM-DD
        schema:
          type: string
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.005000'
      x-free-tier: sample
      x-mcp-tool: companies-house__advanced-search
    servers:
    - url: https://fourzerotwo.si
components:
  responses:
    PaymentRequired:
      description: x402 payment required. The body (also base64 in the PAYMENT-REQUIRED header) lists accepted payments.
      headers:
        PAYMENT-REQUIRED:
          schema:
            type: string
          description: Base64 JSON x402 v2 PaymentRequired
      content:
        application/json:
          schema:
            type: object
            properties:
              x402Version:
                type: integer
              error:
                type: string
              accepts:
                type: array
                items:
                  type: object
    Error:
      description: 400 = invalid input, 404 = not found at the source, 502 = the source failed. Never charged.
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                type: string
              charged:
                type: boolean
  securitySchemes:
    freeKey:
      type: apiKey
      in: header
      name: X-API-Key
      description: Optional free key (fzt_…) for the free tier.
x-refined-from:
- openapi.json
- fourzerotwo-si-openapi.json