> For the complete documentation index, see [llms.txt](https://wiki.dieagenturverwaltung.de/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.dieagenturverwaltung.de/die-agenturverwaltung-en/finanzen-1/kva/abrechnung-von-kostenvoranschlaegen/periodische-teilabrechnung-retainer.md).

# Periodic partial billing (retainer)

## What is a periodic partial billing?

Assume you have concluded a consulting contract with a customer that runs for one year and where it was agreed that one twelfth of the agency service and external service will be billed monthly. \
In addition you granted the customer a discount of 1,000 EUR.\
When you then create one of the monthly invoices, you want to\
a) bill one twelfth of the agency service and external service\
b) carry one twelfth of the granted discount into the invoice

{% hint style="info" %}
For the periodic billing the delivery period of the estimate plays a central role. In our example we assume a delivery period from 01.01 to 31.12.

You set the delivery period in the first tab of your estimate.
{% endhint %}

## This is how you create a periodic partial billing

Select a billing method in the "Billing" tab of the estimate:

![](/files/b732da99d51742a0a7c8406861b6d6cb8bd28f14)

In the next step decide on "Charge lump sum for a period".

![](/files/4d3e33423929cc994dcbed1de5043b40f170f67c)

Then choose a period:

![](/files/8d268a88c748f3bfdb3da6e6d20da6bf1eae86c7)

You can select a month from the service period of your estimate or specify a custom period.

{% hint style="info" %}
**Note**\
It makes a calculational difference whether you select "01.03.2019" to "31.03.2019" here or simply "March 2019".\
With "Custom period" 31 days are billed in this example, whereas with "Month March 2019" one twelfth of the estimate total from our example is billed. If the delivery period of an estimate spans several months, all invoices generated with this billing method **monthly invoices** that **same amount**, although the months have different lengths (28, 29, 30 or 31 days).\
With a delivery period of e.g. six and a half months (01.01. to 15.07) the first 6 invoices are distributed evenly and the half July is billed at the very end.
{% endhint %}

Then optionally enter the desired invoice date and — if different from the estimate — the job, and click "Create invoice now".


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