> ## Documentation Index > Fetch the complete documentation index at: https://docs.goteal.co/llms.txt > Use this file to discover all available pages before exploring further. # Get ONS expenditure > Estimates cost of living and housing from the user's payroll periods, date of birth, and postcode using the Teal V3.0 ONS Family Spending model (table A6). Net pay is split across calendar months by overlapping days. Age is taken as of the last day of each month from that period's date of birth (else the user's) and adjusts cost of living only. Region (from each period's postcode prefix, else the user's first postcode that has an ONS region) adjusts housing only. Months are skipped, not returned, when their net pay is zero or negative (refunds, reversals) or when no postcode for the month has an ONS region (for example GY, JE, IM or an unknown postcode). `404` lists each missing or invalid input as its own string in `errors`: - `User [] not found` - `[date_of_birth] param is missing on the user and its payslips` - `[post_codes] param is missing on the user and its payslips` - `[date_of_birth] param is after the payslip month` - `[date_of_birth] param gives an age over 150, the ONS model limit` - `Postcode has no ONS region; supported: England, Wales, Scotland, Northern Ireland` (only when no month has a postcode with a region) - `payroll periods are missing` - `payroll periods have no positive net pay` Monthly cost of living and housing estimates from the Teal V3.0 ONS Family Spending model (table A6). `expenditures` is newest month first. Cost of living is age-adjusted from each payroll period's `identity_information.date_of_birth`, falling back to the user's `date_of_birth`. Housing is region-adjusted from each period's `identity_information.address.post_code`, falling back to the user's first `post_codes` entry that has an ONS region. Age is calculated as of the last day of each month. Some months are left out of `expenditures`: * Months whose net pay is zero or negative (refunds, reversals). They are skipped rather than returned as `0.00` or negative amounts. * Months where neither the payroll period's postcode nor any of the user's `post_codes` has an ONS region (for example GY, JE, IM or an unknown postcode). `404` returns `{ "errors": [...] }` with one string per missing or invalid input: | Error | Cause | | - | - | | `User [] not found` | No such user for this client | | `[date_of_birth] param is missing on the user and its payslips` | No date of birth on a month's payroll period or on the user | | `[post_codes] param is missing on the user and its payslips` | No postcode on a payroll period or on the user | | `[date_of_birth] param is after the payslip month` | Date of birth is after the month it applies to, for example in the future | | `[date_of_birth] param gives an age over 150, the ONS model limit` | Age is above the model's oldest band | | `Postcode has no ONS region; supported: England, Wales, Scotland, Northern Ireland` | No month has a postcode with an ONS region. One string per postcode tried | | `payroll periods are missing` | No payroll periods with net pay and dates | | `payroll periods have no positive net pay` | Every month has zero or negative net pay | ## OpenAPI ````yaml GET /expenditure/{user_id}/ons openapi: 3.0.1 info: title: Payroll API description: A full flagged payroll api provided by Teal version: 1.0.0 servers: - url: https://api.sandbox.goteal.co description: Sandbox server for experiments - url: https://api.goteal.co description: Production server security: - ApiKeyAuth: [] - MemberBearerAuth: [] paths: /expenditure/{user_id}/ons: get: summary: Returns monthly ONS V3.0 affordability estimates for a user description: > Estimates cost of living and housing from the user's payroll periods, date of birth, and postcode using the Teal V3.0 ONS Family Spending model (table A6). Net pay is split across calendar months by overlapping days. Age is taken as of the last day of each month from that period's date of birth (else the user's) and adjusts cost of living only. Region (from each period's postcode prefix, else the user's first postcode that has an ONS region) adjusts housing only. Months are skipped, not returned, when their net pay is zero or negative (refunds, reversals) or when no postcode for the month has an ONS region (for example GY, JE, IM or an unknown postcode). `404` lists each missing or invalid input as its own string in `errors`: - `User [] not found` - `[date_of_birth] param is missing on the user and its payslips` - `[post_codes] param is missing on the user and its payslips` - `[date_of_birth] param is after the payslip month` - `[date_of_birth] param gives an age over 150, the ONS model limit` - `Postcode has no ONS region; supported: England, Wales, Scotland, Northern Ireland` (only when no month has a postcode with a region) - `payroll periods are missing` - `payroll periods have no positive net pay` parameters: - in: path name: user_id schema: type: string format: uuid required: true description: ID of the user to estimate expenditure for responses: '200': description: Monthly expenditure estimates content: application/json: schema: $ref: '#/components/schemas/OnsExpenditureResponse' example: expenditures: - date: 2026-01-01T12:00Z cost_of_living: '333.21' housing: '372.96' total: '706.17' '401': $ref: '#/components/responses/UnauthorizedApiKey' '404': description: User not found, or required inputs are missing or invalid content: application/json: schema: $ref: '#/components/schemas/Error' example: errors: - >- [date_of_birth] param is missing on the user and its payslips - '[post_codes] param is missing on the user and its payslips' - payroll periods are missing components: schemas: OnsExpenditureResponse: type: object required: - expenditures properties: expenditures: type: array description: One row per calendar month that has allocated net pay items: type: object required: - date - cost_of_living - housing - total properties: date: type: string format: date-time description: First day of the calendar month at UTC noon example: 2026-01-01T12:00Z cost_of_living: type: string description: Age-adjusted cost of living in pounds (2 decimals) example: '333.21' housing: type: string description: Region-adjusted housing in pounds (2 decimals) example: '372.96' total: type: string description: cost_of_living plus housing example: '706.17' Error: required: - errors type: object properties: errors: type: array items: type: string description: An array of messages describing the errors example: - The request is missing the required field `name` Unauthorized: type: object properties: errors: type: string description: An array of messages describing the errors example: - No X-API-KEY header provided or wrong value responses: UnauthorizedApiKey: description: Unauthorized if the X-API-KEY is not provided or is wrong content: application/json: schema: $ref: '#/components/schemas/Unauthorized' securitySchemes: ApiKeyAuth: type: apiKey in: header name: X-API-KEY MemberBearerAuth: type: http scheme: bearer description: >- Bearer token for authentication. The token should be the one returned by the "/members/signin" ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.