---
title: "Generate next invoice number"
method: POST
path: "/v1/invoice-series/{id}/generate"
tags: ["InvoiceSeries"]
---

# Generate next invoice number

`POST /v1/invoice-series/{id}/generate`

Generates and consumes the next sequential invoice number. This operation is atomic and uses pessimistic locking to prevent duplicate numbers in concurrent scenarios.

## Path parameters

- `id` string, required

## Response `200`

Invoice number generated successfully

- string

## Other responses

- `400` — Invoice series not available or inactive
- `401` — Not authorized
- `403` — No access to this invoice series
- `404` — Invoice series not found

---

[API](https://skmtc.net/timesheet/apis/timesheet-api.md) · [All operations](https://skmtc.net/timesheet/apis/timesheet-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/timesheet/timesheet-api/revisions/fbe59bacb638/schema)