How many zones do I need in a smart sprinkler controller?

Match zone count to your existing valve count, plus one or two extra for future drip lines or added beds. Most residential in-ground systems use 6 to 12 zones; larger properties or yards with separate drip, lawn, and landscape circuits often need 16. Buying a 16-zone unit when you only need 8 is generally a waste of money, since unused terminals don't add functionality.