Azure SQL Database costs--forecast doesn't update?

Question

I initially spun up a (very) small database for a small org. It was hosted locally but due to possible expansion and other details, it was decided to migrate this to the cloud. Initially, it was a serverless model and I quickly realized the cost of this per core would be silly given the size of the DB. I changed to the smallest DTS pricing.

The forecast for this still shows 120+ in monthly spend which seems silly for the size of this database--and the accumulated cost over 2 days hasn't changed. Does forecasting not update? I am not familiar (other than trying to get my head around it via YouTube videos) on DTS pricing and want to make sure we don't end up with a 300+ Azure bill over a small (less than 2 gig!) database. Thanks for any help navigating this.

Answer 1

Hello Ryan Geiler

Thank you for posting your query on Microsoft Q&A platform.

Azure Cost Management builds its forecast based on historical usage data, not your current pricing tier in real time. Since you recently switched from the serverless (vCore) model to DTU-based pricing, the forecast is still projecting costs based on the older, more expensive serverless usage pattern. On top of that, cost and usage data typically takes 8–24 hours (and up to 72 hours for pay-as-you-go subscriptions) to flow into Cost Management. So after a tier change, it's completely normal for the forecast to lag behind for several days before it recalibrates.

Costs are estimated until an invoice is generated and the forecast is projected for the Total of all your resources based on what's been collected so far.

What you should actually be paying:

If you selected the Basic DTU tier (which is the smallest), it includes 5 DTUs and 2 GB of storage — which fits your sub-2 GB database perfectly. The Basic tier costs approximately $4.90/month. You're not going to see a $300 bill from this.

How to confirm everything looks right:

1. Go to your SQL Database → Overview in the Azure portal and verify the Pricing tier shows Basic.
2. Navigate to Cost Management + Billing → Cost Analysis, and switch the view to Actual cost (instead of Forecast). Filter by Service name = SQL Database to see what you've actually been charged so far.
3. You can also set up a budget alert so you get notified if spending crosses a threshold you're comfortable with this way you don't have to keep checking manually.

Give it about 3–5 days after the tier change, and the forecast should start reflecting your new DTU pricing accurately.

Reference:

• Understand Cost Management data (data latency and forecast behavior)
• Common cost analysis uses — View forecast costs
• DTU-based purchasing model overview
• DTU resource limits for single databases (Basic/Standard/Premium tiers)
• Plan and manage costs for Azure SQL Database
• Create and manage budgets

Hope that clears things up — you're on the right track with the Basic DTU tier for a small database like this.

Thanks,

Suchitra.

Answer 2

Hello Ryan !

Thank you for posting on MS Learn Q&A.

That may be a forecast delay or a historical estimate effect and not necessarily your final bill.

Azure Cost Management forecast is not a live quote based only on the current database size or current SKU and the forecast costs are based on historical resource use and Cost Management data can lag.

EA/MCA data is typically available between 8 and 24 hours while pay as you go can take up to 72 hours.

https://learn.microsoft.com/en-us/azure/cost-management-billing/costs/cost-analysis-common-uses

For Azure SQL Database, the DTU model is a fixed bundle of compute, storage and I/O.

Single databases in DTU tiers are billed hourly based on the selected service tier or compute size.

The basic tier is 5 DTUs with 2 GB included max storage while standard S0 is 10 DTUs with 250 GB included storage. So for a database under 2 GB basic may be enough if the workload is light. ([Microsoft Learn](https://learn.microsoft.com/en-us/azure/azure-sql/database/service-tiers-dtu?view=azuresql"DTU-Based Purchasing Model - Azure SQL Database | Microsoft Learn"))

You can change to daily costs and filter service name = Azure SQL Database.

Group by Resource then also check Meter or Service tier.

You can use the Azure Pricing Calculator with your exact region and tier. https://azure.microsoft.com/en-us/pricing/details/azure-sql-database/single/