> For the complete documentation index, see [llms.txt](https://developer.smarts.ee/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.smarts.ee/integration/custom-integration/invoice.md).

# Invoicing

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Implementation is **OPTIONAL**
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Smarts will store detailed confirmation invoice only for two months. So it is important to save detailed invoice copy.

### Implementation

Implement according endpoints

[**Receive invoice endpoint**](/integration/custom-integration/invoice/receive-invoice.md)