Database Activity

Back Up How Often

Low to medium activity

Full -- once per week
Differential -- once per day
Transaction Log -- every 8-10 hours

High activity (small to medium size)

Full -- twice per week
Differential -- twice per day
Transaction Log -- every 2-4 hours

High activity (large size-Full or Bulk-Logged Recovery model)

Full -- once per week
Differential -- once per day
Transaction Log -- every 60 minutes

High activity (large size, Simple Recovery model)

Full -- once per week