# The periodic invoicing ## Context: Testo orders a corner sofa for its new premises. In accordance with the agreement, an invoice will be sent to it every month. ## Implementation in Simax The first thing to do is to set Testo's billing frequency. To do this, go to **Sales > Customer > Customers**, then **\[Conditions]**, **|Periodic invoicing|**, and select “Monthly.”

The next invoice date is 12/01/2024, calculated automatically. As before, we will create the order and **\[\[Save]]**.

Then, we prepare the order in **Sales> Order> Orders**, by selecting the order and clicking on **\[\[Preparation voucher]]**.

We choose the preparer, then **\[\[ok]]**.

And let's validate it.

And finally, we save the delivery note.

An invoice line is then created on 11/11/2024 in **Sales > Invoicing > Lines to invoice.**

Please note that each time a delivery note is issued in favor of Testo, an associated invoice line will be created and issued on the next invoice date. To invoice, simply select the line to be invoiced and click on **\[\[Single Invoice]]**. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://doc.simax.fr/documentation-simax-anglais/invoicing/the-periodic-invoicing.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.