> ## Documentation Index > Fetch the complete documentation index at: https://docs.ruddr.io/llms.txt > Use this file to discover all available pages before exploring further. # Create a project invoice milestone Scheduled invoicing for a fixed fee project. This is only available for projects that have a billing type of "fixed" or "fixed\_recurring". ## OpenAPI ````yaml openapi.json POST /project-invoice-milestones openapi: 3.1.0 info: title: Ruddr API version: '1.0' license: name: Proprietary url: https://www.ruddr.com/master-subscription-agreement servers: - url: https://www.ruddr.io/api/workspace security: - bearerAuth: [] tags: - name: Allocations description: Manage resource allocations for scheduling team members to projects. - name: Availability Periods description: Manage member availability periods for capacity planning. - name: Business Units description: >- Manage business units for organizing invoice settings and grouping clients and projects. - name: Client Roles description: Manage client roles and their billing terms. - name: Client Tags description: Manage tags for categorizing clients. - name: Clients description: Manage clients and their billing settings. - name: Companies description: Manage companies in the CRM pipeline. - name: Company Spend Tiers description: Manage spend tier classifications for companies. - name: Company Types description: Manage type classifications for companies. - name: Contact Tags description: Manage tags for categorizing contacts. - name: Contacts description: Manage contacts associated with clients, companies, and opportunities. - name: Cost Periods description: Manage member cost rate periods for profitability tracking. - name: Credit Notes description: View credit notes issued against invoices. - name: Disciplines description: Manage disciplines for classifying member skill areas. - name: Exchange Rate description: Get exchange rates for multi-currency workspaces. - name: Exchange Rate Periods description: Manage custom exchange rate periods for currency conversion. - name: Expense Categories description: Manage expense categories for tracking and reporting. - name: Expense Items description: Manage individual expense line items. - name: Expense Reports description: Manage expense reports submitted by members. - name: Holiday Schedules description: Manage holiday schedules for capacity and availability planning. - name: Holidays description: Manage individual holidays within holiday schedules. - name: Industries description: Manage industry classifications for clients and companies. - name: Invoice Items description: Manage invoice line item types for billing. - name: Invoices description: View invoices and their line items. - name: Job Titles description: Manage job title classifications for members. - name: Locations description: Manage office locations for members and projects. - name: Member Certifications description: Manage certification types that can be assigned to members. - name: Member Levels description: Manage member level classifications for career tracking. - name: Member Tags description: Manage tags for categorizing members. - name: Members description: Manage workspace members and their profiles. - name: Opportunities description: Manage sales opportunities in the CRM pipeline. - name: Opportunity Pipelines description: Manage pipelines for tracking opportunity stages. - name: Opportunity Lead Sources description: Manage lead source classifications for opportunities. - name: Opportunity Stages description: Manage pipeline stage definitions for opportunities. - name: Opportunity Tags description: Manage tags for categorizing opportunities. - name: Opportunity Types description: Manage type classifications for opportunities. - name: Payment Methods description: Manage payment method options for invoices. - name: Payments description: View payments received against invoices. - name: Pipeline Activities description: >- Manage pipeline activities associated with companies, contacts, members, and opportunities. - name: Pipeline Activity Types description: Manage activity type classifications for pipeline activities. - name: Practices description: Manage practice area classifications for organizing projects and members. - name: Project Budget Expenses description: Manage expense budget line items on projects. - name: Project Budget Other Items description: Manage other budget line items on projects. - name: Project Budget Product Items description: Manage product budget line items on projects. - name: Project Budget Service Items description: Manage additional service budget line items on projects. - name: Project Expenses description: Manage project-level expense line items. - name: Project Groups description: View project groups for organizing related projects. - name: Project Health Reports description: Manage project health status reports. - name: Project Invoice Milestones description: Manage invoice milestones for fixed-fee project billing. - name: Project Members description: Manage team member assignments on projects. - name: Project Monthly Budget Expenses description: Manage monthly expense budget line items on projects. - name: Project Monthly Budget Other Items description: Manage monthly other budget line items on projects. - name: Project Monthly Budget Product Items description: Manage monthly product budget line items on projects. - name: Project Monthly Budget Service Items description: Manage monthly additional service budget line items on projects. - name: Project Other Items description: Manage project-level other item line items. - name: Project Product Items description: Manage project-level product line items. - name: Project Revenue Adjustments description: Manage earned revenue adjustments for projects. - name: Project Revenue Recognition Entries description: Manage revenue recognition entries for projects. - name: Project Roles description: Manage roles defined on projects for billing and staffing. - name: Project Service Items description: Manage project-level additional service line items. - name: Project Tags description: Manage tags for categorizing projects. - name: Project Tasks description: Manage tasks on projects for time tracking and planning. - name: Project Types description: Manage type classifications for projects. - name: Projects description: Manage projects and their settings. - name: Resource Placeholders description: Manage placeholder resources for allocation planning. - name: Security Roles description: View security roles for assigning member permissions. - name: Skills description: Manage skill classifications for members and resource planning. - name: Task Categories description: Manage task category classifications for project tasks. - name: Task Tags description: Manage tags for categorizing project tasks. - name: Task Templates description: Manage reusable task templates for projects. - name: Tax Rates description: Manage tax rates for invoicing. - name: Time Entries description: Manage time entries for tracking hours on projects. - name: Time Off Types description: Manage time off type classifications. - name: Timesheet Attestations description: Manage attestation statements members sign when submitting timesheets. - name: Timesheets description: Manage timesheet submissions for tracking hours across a period. - name: Utilization Target Periods description: Manage member utilization target periods for capacity planning. - name: Workspace Roles description: Manage workspace-level roles for billing rate configuration. paths: /project-invoice-milestones: post: tags: - Project Invoice Milestones summary: Create a project invoice milestone operationId: create-a-project-invoice-milestone requestBody: content: application/json: schema: type: object required: - projectId - invoiceItemId - date - name properties: typeId: type: string description: >- The type of invoice milestone. Identifies whether the milestone is one-off (`"custom"`, the default) or recurring (`"recurring"`). enum: - custom - recurring date: type: string description: The date of the milestone. Must be in the form YYYY-MM-DD. format: date quantity: type: - number - 'null' description: >- The quantity for calculating the `fee`. Required when `rate` is provided. rate: type: - number - 'null' description: >- The rate for calculating the `fee`. Required when `quantity` is provided. fee: type: number description: >- The total amount for the milestone. Required when `quantity` and `rate` are not provided. name: type: string description: The name of the milestone (max 255 chars). projectId: type: string description: >- The project ID (`uuid`) for this milestone. Must be a `fixed` or `fixed_recurring` billing type project. invoiceItemId: type: string description: The invoice item ID (`uuid`) for this milestone. responses: '200': description: '200' content: application/json: schema: $ref: '#/components/schemas/ProjectInvoiceMilestone' examples: Result: value: id: 7f3e1a2d-94b8-4c6e-b3f1-d52a8e0c7b94 typeId: custom date: '2026-04-01' quantity: 1 rate: 15000 fee: 15000 name: Phase 1 Delivery createdAt: '2026-03-03T09:15:00.000Z' project: id: d077258e-2158-4f34-aabd-97e971d0c18d name: Cloud Infrastructure Services client: id: aa39afdb-e168-4956-b061-41c7c62e8c2e name: Paul's Boutique invoiceItem: id: aba04832-216c-463e-8998-c520948f707c name: Consulting Services invoiced: false '400': description: '400' content: application/json: schema: $ref: '#/components/schemas/ValidationErrorResponse' examples: Validation: value: status: 400 message: >- There was a problem processing your request. See errors for more details. errors: - '''name'' is required' InvalidData: value: status: 400 message: >- 'projectId' '712a5c6a-5d3c-4c2b-abed-bbd73de7f986' does not match a valid project. deprecated: false components: schemas: ProjectInvoiceMilestone: type: object properties: id: type: string description: The unique identifier for the object. typeId: type: string description: >- The type of invoice milestone. Identifies whether the milestone is one-off (`"custom"`, the default) or recurring (`"recurring"`). enum: - custom - recurring date: type: string format: date description: The date of the milestone. Will be in the form YYYY-MM-DD. quantity: type: - number - 'null' description: The quantity used to calculate the `fee`. rate: type: - number - 'null' description: The rate used to calculate the `fee`. fee: type: number description: The total amount for the milestone. name: type: string description: The name of the milestone. createdAt: type: string format: date-time description: The timestamp when the object was created. project: type: object description: The project this milestone belongs to. properties: id: type: string description: The unique identifier for the object. name: type: string description: The name of the project. client: type: object description: The client associated with the project. properties: id: type: string description: The unique identifier for the object. name: type: string description: The name of the client. invoiceItem: type: object description: The invoice item associated with this milestone. properties: id: type: string description: The unique identifier for the object. name: type: string description: The name of the invoice item. invoiced: type: boolean description: Whether the milestone has been invoiced. ValidationErrorResponse: type: object properties: status: type: integer description: The HTTP status code. message: type: string description: A human-readable error message. errors: type: array description: A list of validation error messages. items: type: string securitySchemes: bearerAuth: type: http scheme: bearer ````