Originally announced @ TechEd 2010

http://blogs.msdn.com/b/cbiyikoglu/archive/2010/06/10/pricing-for-the-new-large-sql-azure-databases-explained.aspx

Excerpt follows

Assume we have a a web edition database that has a MAXSIZE=5GB. If the database size is 800MB, the daily charge for the database will be at the 1GB rate for web edition. if the next day, the database size grows to 3GBs, the daily charge will be based on the next billing increment for web edition which is 5GB for that day. If the next day, after some data deletion, the size drops back to 900MB, the daily charge will be based on 1GB back again.

The same example applies to a business edition edition database. Assume we have a business edition database with MAXSIZE=50GB. If the total database size is 8GB, the daily charge for the database will be at the 10GB rate. If the next day, the database size grows to 25GB, the daily charge will be based on the next billing increment for the business edition which is 30GB and so on.

- Cost Predictability Enhancements: Even though both editions can grow to larger ceiling sizes (such as 50GB), you can cap the data size per database and control your bill at the billing increments. MAXSIZE option for CREATE/ALTER DATABASE will help set the cap on the size of the database. If the size of your database reaches to the cap set by MAXSIZE, you will receive an error code 40544. You will only be billed for the MAXSIZE amount for the day. When database reaches the MAXSIZE limit, you cannot insert or update data, or create new objects, such as tables, stored procedures, views, and functions. However, you can still read and delete data, truncate tables, drop tables and indexes, and rebuild indexes.

http://www.microsoft.com/windowsazure/pricing/#sql

Pricing at time of article on Tuesday 12th October 2010

• Web Edition:
  • Up to 1 GB relational database = $9.99 / month
  • Up to 5 GB relational database = $49.95 / month**
• Business Edition:
  • Up to 10 GB relational database = $99.99 / month
  • Up to 20 GB relational database = $199.98 / month**
  • Up to 30 GB relational database = $299.97 / month**
  • Up to 40 GB relational database = $399.96 / month**
  • Up to 50 GB relational database = $499.95 / month**
• Data transfers = $0.10 in / $0.15 out / GB – ($0.30 in / $0.45 out / GB in Asia)*

* No charge for inbound data transfers during off-peak times through October 31, 2010