aid: twentyci
url: https://raw.githubusercontent.com/api-evangelist/twentyci/refs/heads/main/apis.yml
name: TwentyCi
kind: company
description: TwentyCi is a United Kingdom residential property data and home-mover
  intelligence company. It aggregates roughly 31.5 million UK addresses and tens of
  billions of data points from hundreds of primary sources into the DOMUS property
  database, and sells that data to estate agents, lenders, insurers, conveyancers,
  house builders, retailers and media agencies through the TwentyCi, TwentyEA and
  TwentyConvey brands. In the UK value chain it sits on the data-supply side rather
  than the listing side - there is no UK MLS, listings are controlled by the
  Rightmove and Zoopla portals, and TwentyCi is one of the private aggregators that
  resells transaction, valuation and home-mover signal on top of that closed market.
  Its API posture is honest but commercial - TwentyAPI is a genuine RESTful v2 API
  at https://api.twentyci.co.uk/api/v2 with a live, publicly readable documentation
  portal covering roughly 57 documented operations across properties, AVM valuation,
  transaction triggers, agent performance, address matching, schools, housing market
  metrics and retail propensity - but every endpoint returns 401 without a
  TwentyCi-issued OAuth 2.0 bearer token, there is no self-serve signup, no published
  pricing, and the specification download TwentyCi advertises at
  https://api.twentyci.co.uk/docs/v2/spec.json returns HTTP 404. Access is
  sales-led and partner-only. RESO is entirely absent - the UK has no MLS or RESO
  regime and TwentyCi identifies property by UPRN, the Ordnance Survey/GeoPlace
  Unique Property Reference Number, rather than by any RESO Universal Property
  Identifier.
image: https://www.twentyci.co.uk/favicon.ico
tags:
- Real Estate
- United Kingdom
- PropTech
- Property Data
- Valuation
- AVM
- Rentals
- Address Data
- Conveyancing
- Homemover Data
- Agent Performance
- Data as a Service
created: '2026-07-26'
modified: '2026-07-26'
specificationVersion: '0.19'
apis:
- aid: twentyci:twentyapi-oauth-token-api
  name: TwentyAPI OAuth Token API
  description: >-
    The single documented authentication endpoint for TwentyAPI. Exchanges a
    TwentyCi-issued client_id, client_secret, username and password for a bearer
    access token and refresh token, which is then presented in an Authorization
    header as "Bearer <token-key>". TwentyCi labels the scheme OAuth2 with an
    Implicit flow while documenting a resource-owner password-credentials request
    body; the only documented scope value is "*". No OpenID Connect discovery
    document is served.
  humanURL: https://api.twentyci.co.uk/documentation#authorisation-for-api-requests
  baseURL: https://api.twentyci.co.uk
  tags:
  - Authentication
  - OAuth
  - Bearer Token
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-oauth-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#authorisation-for-api-requests
- aid: twentyci:twentyapi-properties-api
  name: TwentyAPI Properties API
  description: The core DOMUS property surface of TwentyAPI. Retrieves property
    information and detail by UPRN, recent sales and comparable properties for sale
    in the area, average property values and AVM valuation for a single property,
    postcode and radius search, property attributes, Google Maps imagery URLs,
    transaction history, transport links, planning permission data, floor plans,
    price-per-square-foot comparables and a likely-to-sell propensity signal.
  humanURL: https://api.twentyci.co.uk/documentation#properties
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Property Data
  - Valuation
  - AVM
  - UPRN
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#properties
- aid: twentyci:twentyapi-agent-performance-api
  name: TwentyAPI Agent Performance API
  description: Estate-agent and letting-agent benchmarking built on TwentyCi sales
    and rental data. Ranks brands by SSTC, new instructions, exchange, PIPA
    (percentage of initial price achieved) and days from new instruction to SSTC,
    and returns per-brand statistics for listing value, sold percentage, sale-price
    difference against all other brands, time to sell, let-agreed volumes, time to
    let and let ratios.
  humanURL: https://api.twentyci.co.uk/documentation#agent-performance
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Agent Performance
  - Benchmarking
  - Rentals
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#agent-performance
- aid: twentyci:twentyapi-trigger-information-api
  name: TwentyAPI Trigger Information API
  description: Home-mover event triggers - the transaction-lifecycle signals TwentyCi
    is built on. Retrieves a specific trigger, lists properties by trigger type
    (including properties with no UPRN), and returns the trigger history for a
    property.
  humanURL: https://api.twentyci.co.uk/documentation#trigger-information
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Homemover Data
  - Triggers
  - Events
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#trigger-information
- aid: twentyci:twentyapi-categories-api
  name: TwentyAPI Categories API
  description: Lists the attribute categories available for a property and returns a
    specific category, providing the vocabulary that the Properties API's attribute
    endpoints are organised around.
  humanURL: https://api.twentyci.co.uk/documentation#categories
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Categories
  - Metadata
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#categories
- aid: twentyci:twentyapi-address-match-api
  name: TwentyAPI Address Match API
  description: Partial address matching. Submits a fragmentary or unstructured UK
    address to a match-address process and resolves it against TwentyCi's addressing
    layer, the capability marketed as AddressMaster / Inscriptio address enhancement.
  humanURL: https://api.twentyci.co.uk/documentation#address-match
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Address Data
  - Matching
  - Data Quality
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#address-match
- aid: twentyci:twentyapi-schools-api
  name: TwentyAPI Schools API
  description: Returns nearby schools for a given UK postcode, one of the
    neighbourhood-context datasets TwentyCi layers onto a property record.
  humanURL: https://api.twentyci.co.uk/documentation#schools
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Schools
  - Location Data
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#schools
- aid: twentyci:twentyapi-uk-housing-market-metrics-api
  name: TwentyAPI UK Housing Market Metrics API
  description: Aggregate UK housing market metrics for a specified timeframe -
    new instructions, SSTCs (sold subject to contract) and PCDs (predicted to
    complete date) - the market-level view behind TwentyCi's published Property and
    Homemover Report.
  humanURL: https://api.twentyci.co.uk/documentation#uk-housing-market-metrics
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Market Data
  - Housing Market
  - Analytics
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#uk-housing-market-metrics
- aid: twentyci:twentyapi-this-is-now-api
  name: TwentyAPI This is Now API
  description: "\"This is Now\" retail propensity to buy goods. Local and national
    search endpoints returning consumer propensity signal derived from home-mover
    events, aimed at retailers and media agencies targeting people who have just
    moved."
  humanURL: https://api.twentyci.co.uk/documentation#this-is-now-retail-propensity-to-buy-goods
  baseURL: https://api.twentyci.co.uk/api/v2
  tags:
  - Retail
  - Propensity
  - Marketing Data
  properties:
  - type: OpenAPI
    url: openapi/twentyci-twentyapi-openapi.json
  - type: Documentation
    url: https://api.twentyci.co.uk/documentation#this-is-now-retail-propensity-to-buy-goods
common:
- type: AgenticAccess
  url: agentic-access/twentyci-agentic-access.yml
- type: DomainSecurity
  url: security/twentyci-domain-security.yml
- type: OAuthScopes
  url: scopes/twentyci-scopes.yml
- type: Authentication
  url: authentication/twentyci-authentication.yml
- type: Vocabulary
  url: vocabulary/twentyci-vocabulary.yml
- type: Conventions
  url: conventions/twentyci-conventions.yml
- type: ErrorCatalog
  url: errors/twentyci-problem-types.yml
- type: Examples
  url: examples/twentyci-examples.yml
- type: DataModel
  url: data-model/twentyci-data-model.yml
- type: Lifecycle
  url: lifecycle/twentyci-lifecycle.yml
- type: Conformance
  url: conformance/twentyci-conformance.yml
- type: Compliance
  url: https://www.twentyci.co.uk/privacy-policy/
- type: Packages
  url: packages/twentyci-packages.yml
- type: MCPServer
  url: mcp/twentyci-mcp.yml
- type: AgentSkill
  url: skills/_index.yml
- type: LLMsTxt
  url: llms/twentyci-llms.txt
- type: Overlay
  name: TwentyAPI v2 enhancements
  url: overlays/twentyci-twentyapi-overlay.yaml
- type: Overlay
  name: TwentyAPI OAuth token enhancements
  url: overlays/twentyci-twentyapi-oauth-overlay.yaml
- type: Website
  url: https://www.twentyci.co.uk/
- type: DeveloperPortal
  url: https://api.twentyci.co.uk/documentation
- type: Documentation
  url: https://api.twentyci.co.uk/documentation
- type: APIReference
  url: https://api.twentyci.co.uk/documentation#properties
- type: GettingStarted
  url: https://api.twentyci.co.uk/documentation#overview
- type: Contact
  url: https://www.twentyci.co.uk/contact/
- type: About
  url: https://www.twentyci.co.uk/about-us/
- type: Blog
  url: https://news.twentyci.co.uk/blog
- type: BlogRSS
  url: https://www.twentyci.co.uk/feed/
- type: PrivacyPolicy
  url: https://www.twentyci.co.uk/privacy-policy/
- type: CookiePolicy
  url: https://www.twentyci.co.uk/cookies-policy/
- type: SustainabilityPolicy
  url: https://www.twentyci.co.uk/sustainability-policy/
- type: Careers
  url: https://www.twentyci.co.uk/careers/
- type: LinkedIn
  url: https://www.linkedin.com/company/twentyci/
- type: Twitter
  url: https://twitter.com/TwentyCi
- type: Facebook
  url: https://www.facebook.com/TwentyCi
- type: GitHubOrganization
  url: https://github.com/twentyci
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com