> ## Documentation Index > Fetch the complete documentation index at: https://docs.revdesk.com/llms.txt > Use this file to discover all available pages before exploring further. # Register phone numbers with the Free Caller Registry > Submits US numbers to the Free Caller Registry, which feeds the analytics engines used by T-Mobile, AT&T and Verizon for spam labeling (Hiya, TNS, First Orion). Numbers hosted on RevDesk are included free; bring-your-own numbers bill $5/number per calendar month as a Number Registration line item on your invoice, starting when the registry accepts the submission. Requires an authorization attestation — you must be entitled to register these numbers for the business they belong to. Business identity defaults to your workspace's caller-trust profile; override per-request with business_identity. Async: poll GET /v1/number-registrations or subscribe to registration_submitted / registration_confirmed / registration_failed webhooks. Re-registering an already-live number is free and refreshes it. ## OpenAPI ````yaml /openapi.json post /v1/number-registrations openapi: 3.1.0 info: title: RevDesk v1 API version: 1.0.0 description: >- Programmatic access to the RevDesk voice platform — calls, numbers, caller trust, and brands. contact: name: RevDesk email: support@revdesk.com servers: - url: https://api.revdesk.com security: - bearerAuth: [] tags: - name: Phone Numbers - name: Caller IDs - name: Enterprise Registration - name: Branded Calling - name: Calls - name: SMS - name: WebRTC - name: Reputation - name: Usage - name: Account - name: Agents - name: Documents - name: Number Registration - name: Sub-entities paths: /v1/number-registrations: post: tags: - Number Registration summary: Register phone numbers with the Free Caller Registry description: >- Submits US numbers to the Free Caller Registry, which feeds the analytics engines used by T-Mobile, AT&T and Verizon for spam labeling (Hiya, TNS, First Orion). Numbers hosted on RevDesk are included free; bring-your-own numbers bill $5/number per calendar month as a Number Registration line item on your invoice, starting when the registry accepts the submission. Requires an authorization attestation — you must be entitled to register these numbers for the business they belong to. Business identity defaults to your workspace's caller-trust profile; override per-request with business_identity. Async: poll GET /v1/number-registrations or subscribe to registration_submitted / registration_confirmed / registration_failed webhooks. Re-registering an already-live number is free and refreshes it. operationId: v1_number_registrations_post parameters: - name: Idempotency-Key in: header required: false description: >- UUID — when present, deduplicates repeat submissions. See /api-reference/idempotency. schema: type: string requestBody: required: true content: application/json: schema: $schema: http://json-schema.org/draft-07/schema# type: object properties: phone_numbers: minItems: 1 maxItems: 1000 type: array items: type: string pattern: ^\+1\d{10}$ attestation: type: object properties: authorized_to_register: type: boolean const: true required: - authorized_to_register additionalProperties: false business_identity: type: object properties: business_name: type: string minLength: 1 maxLength: 255 street_address: type: string minLength: 1 maxLength: 255 city: type: string minLength: 1 maxLength: 100 state: type: string minLength: 2 maxLength: 50 zip: type: string minLength: 3 maxLength: 12 website: type: string format: uri contact_name: type: string minLength: 1 maxLength: 120 contact_phone: type: string call_purpose: type: string minLength: 1 maxLength: 500 additionalProperties: false monthly_call_volume: type: string maxLength: 40 required: - phone_numbers - attestation additionalProperties: false responses: '200': description: Success content: application/json: schema: $schema: http://json-schema.org/draft-07/schema# type: object properties: data: type: object properties: submission_ids: type: array items: type: string registrations: type: array items: type: object properties: registration_id: type: string phone_number: type: string status: type: string source: type: string hosted: type: boolean monthly_rate_dc: type: number registered_at: anyOf: - type: string - type: 'null' cancelled_at: anyOf: - type: string - type: 'null' created_at: type: string required: - registration_id - phone_number - status - source - hosted - monthly_rate_dc - registered_at - cancelled_at - created_at additionalProperties: false required: - submission_ids - registrations additionalProperties: false required: - data additionalProperties: false '400': description: Validation error content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' '403': description: Forbidden content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' '404': description: Not found content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' '409': description: Conflict (incl. idempotency conflicts) content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' '429': description: Rate limited content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' components: schemas: ErrorEnvelope: type: object properties: error: type: object required: - code - message properties: code: type: string message: type: string fields: type: object additionalProperties: type: string doc_url: type: string format: uri securitySchemes: bearerAuth: type: http scheme: bearer ````