It’s a bit hard to know the version numbers for Expression Blend releases as the information is scattered about the Internet.
| Version Name | Number | Release Date |
| Expression Blend 4, original release | 4.0 | June 7, 2010 |
| Expression Blend 4 Service Pack 1 (SP1) | 4.0.20901.0 | Sept 7, 2010 |
| Windows Phone SDK 7.1 version |
4.0.30816.0 |
Sept 28,2011 |
| Microsoft Expression Blend Preview for Silverlight 5 | 4.1.10819.0 | Sept 9, 2011 |
