Hello Sander van Dijk,
Welcome to the Microsoft Q&A forum.
The pre-purchase plan allows you to save up to 37%(compared to pay-as-you-go pricing) on your DBU costs when you pre-purchase Azure Databricks commit units (DBU) for one or three years
You can use the pre-purchased DBUs at any time during the purchase terms.
To check whether pre-purchasing DBUs is expedient for you, you can use the Azure pricing calculator to estimate your costs based on your current program with Microsoft
You can also contact your Azure sales specialist for pricing details.
Please check this below reference documents:
https://azure.microsoft.com/en-us/pricing/details/databricks/
I hope this answers your question.
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