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## Resource: Introduction

## Article: Introduction

## Article Link: https://dev.wix.com/docs/api-reference/business-management/get-paid/invoices/invoices-settings/introduction.md

## Article Content:

# About the Invoices Settings API

Invoice settings control how invoice numbers are generated for a site. Each site has a single invoice settings entity that's automatically available. No creation step is required. You can retrieve and update the settings at any time.

With the Invoices Settings API, you can:

- Retrieve invoice settings for a site.
- Configure invoice numbering with a custom prefix, suffix, and starting number.

Invoice numbers are formatted as `{prefix}{nextNumber}{suffix}`. For example, with prefix `INV-`, next number `1001`, and suffix `-2024`, the invoice number is `INV-1001-2024`. Only 1 prefix and suffix are active at a time. Each prefix has its own independent counter—switching to a different prefix starts a new sequence for that prefix. If you switch back to a previously used prefix, its counter continues from the highest number already issued for that prefix.

## Before you begin

It's important to note the following points before starting to code:

- Only 1 invoice settings entity exists per site. There's no ID field because the entity is unique per site.
- Invoice settings can't be deleted.
- You can only retrieve or update invoice settings. There are no create, delete, or query methods.
- You can't set `nextNumber` lower than the highest number already used for the current prefix.

## Use cases

- [Configure invoice numbering for a business](https://dev.wix.com/docs/api-reference/business-management/get-paid/invoices/invoices-settings/sample-flows.md#configure-invoice-numbering-for-a-business)

## Terminology

- **Invoice settings**: Site-level configuration for invoice numbering. Only 1 entity exists per site.
- **Numbering**: Configuration for how invoice numbers are generated, including prefix, suffix, and the next number in the sequence.

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