How to change default backup setting to compress for a SQL Server?

Use below code to change default backup setting to compress for a SQL Server:

EXEC sys.sp_configure N'backup compression default', N'1'

GO

RECONFIGURE WITH OVERRIDE

GO

Alternately you can perform same operation from GUI by navigating to following path:

Open Properties of the Server à Select Database Setting Page à Check Compress Backup option.

Note: Backup compression is available in only SQL 2008 Enterprise edition onwards.