Matt Robertshaw has a few tips for saving money in Azure:
4. Enterprise Dev/Test subscriptions
Enterprise Dev/Test subscriptions are provided as part of Microsoft Enterprise Agreements (EA). They’re designed for teams of Visual Studio subscribers to run development and test workloads in Azure but at discounted rates, specifically on Windows virtual machines and exclusive gallery images. This is significant because I see many clients using regular Azure subscriptions for development and test, which means they’re potentially paying more than they need to.
One additional point I’d make, though it kind of fits in with points 7 and 9, is to try to make your own services “cloud-first.” In other words, a typical cloud migration takes services built for on-prem data centers, converts the servers into VMs, ships those VMs up into Azure/AWS/Google/whatever, and then you end up paying more than you did on-prem.
Instead, read up a bit on cloud architecture and see how you might be able to change a service to fit that model. Instead of having a server running all the time, is it possible to store messages in a queue and have functions process these messages on a given schedule? Can you use expensive tools like Azure Synapse Analytics to perform nightly data processing and move the results to a much less expensive Azure SQL Database?