> ## Documentation Index > Fetch the complete documentation index at: https://docs.conversion.ai/llms.txt > Use this file to discover all available pages before exploring further. # Batch Add Campaign Members > Add up to 200 members to a custom campaign by email, creating contacts that do not exist yet. Adding is an idempotent upsert: a contact already in the campaign has its status updated instead of being added twice. Status progression is forward-only for existing members; requesting their current or an earlier status leaves it unchanged. Set a status by `statusId` or `status` from `GET /v2/campaigns/{campaignId}`, or omit both to use the campaign type's first status. Members are processed independently, so one can fail while the rest of the batch succeeds. ## OpenAPI ````yaml /openapi.json post /v2/campaigns/{campaignId}/members/batch openapi: 3.1.0 info: title: Conversion API version: 2.0.0 description: >- The Conversion API lets you programmatically manage contacts, track custom events, and manage their associated data. servers: - url: https://pub-api.conversion.ai/api security: - apiKey: [] paths: /v2/campaigns/{campaignId}/members/batch: post: summary: Batch Add Campaign Members description: >- Add up to 200 members to a custom campaign by email, creating contacts that do not exist yet. Adding is an idempotent upsert: a contact already in the campaign has its status updated instead of being added twice. Status progression is forward-only for existing members; requesting their current or an earlier status leaves it unchanged. Set a status by `statusId` or `status` from `GET /v2/campaigns/{campaignId}`, or omit both to use the campaign type's first status. Members are processed independently, so one can fail while the rest of the batch succeeds. operationId: batchAddCampaignMembers parameters: - name: campaignId in: path required: true schema: type: string format: uuid description: The Conversion campaign id, as returned by `GET /v2/campaigns`. examples: campaign: value: b7c8d9e0-f1a2-3456-bcde-f01234567890 requestBody: required: true content: application/json: schema: type: object required: - members properties: members: type: array minItems: 1 maxItems: 200 description: An array of members to add to the campaign. items: type: object required: - email properties: email: type: string format: email description: >- The member's email address, normalized (trimmed and lowercased) before matching. An invalid email fails that member's row with `invalid_email` and creates no contact. examples: - jane@example.com statusId: type: string format: uuid description: >- The campaign status id to place the member in, as returned by `GET /v2/campaigns/{campaignId}`. Takes precedence over `status`. An id that is not a status of the campaign's type fails that member's row. examples: - 8f9a0b1c-2d3e-4f4a-9b5c-6d7e8f9a0b1c status: type: string description: >- The campaign status name, case-insensitive. Used only when `statusId` is not set. examples: - Attended examples: add-members: summary: Add members with different statuses value: members: - email: jane@example.com - email: john@example.com status: Attended - email: sam@example.com statusId: 8f9a0b1c-2d3e-4f4a-9b5c-6d7e8f9a0b1c responses: '200': description: >- Batch processed. Check the counts and each result for per-member success or failure. content: application/json: schema: type: object properties: data: type: object required: - processed - succeeded - failed - results properties: processed: type: integer description: The total number of members in the batch. succeeded: type: integer description: The number of members added or updated. failed: type: integer description: The number of members that failed. results: type: array description: >- An array of result objects in the same order as the input `members` array. items: type: object required: - email - success properties: email: type: string description: The member's email address from the request. success: type: boolean description: >- `true` if the member was successfully added or updated. campaignMemberId: type: string format: uuid description: The campaign member id. Present on success. contactId: type: string format: uuid description: >- The id of the member's contact, created if it did not exist. Present on success. error: type: string description: >- A machine-readable error code. Present on failure: `invalid_email`, `invalid_campaign_status`, or `upsert_failed`. message: type: string description: >- A human-readable error description. Present on failure. examples: mixed-results: summary: Partial success value: data: processed: 2 succeeded: 1 failed: 1 results: - email: jane@example.com success: true campaignMemberId: 0a1b2c3d-4e5f-4a6b-8c7d-8e9f0a1b2c3d contactId: a1b2c3d4-e5f6-7890-abcd-ef1234567890 - email: john@example.com success: false error: invalid_campaign_status message: status is not valid for this campaign '400': description: The request was malformed. content: application/json: schema: $ref: '#/components/schemas/Error' examples: invalid-request: summary: Invalid request body value: error: code: invalid_request message: request validation failed '401': description: Authentication failed. content: application/json: schema: $ref: '#/components/schemas/Error' examples: unauthorized: summary: Missing or invalid API key value: error: code: unauthorized message: API key is required '404': description: The requested resource was not found. content: application/json: schema: $ref: '#/components/schemas/Error' examples: campaign-not-found: summary: Campaign not found value: error: code: campaign_not_found message: campaign not found '500': description: An unexpected server error occurred. content: application/json: schema: $ref: '#/components/schemas/Error' examples: internal: summary: Internal error value: error: code: internal_error message: failed to add campaign members components: schemas: Error: type: object properties: error: type: object required: - code - message properties: code: type: string description: A machine-readable error code. examples: - invalid_email message: type: string description: A human-readable error description. examples: - 'invalid email format: not-an-email' securitySchemes: apiKey: type: apiKey in: header name: X-API-Key description: >- Your Conversion API key. Found in **Settings > Integrations** in the dashboard. Format: `sk_live__`. ````