Avast offers three different subscription plans: Avast Free, Avast Premium Security, and Avast Ultimate.
Avast Free will cost you absolutely nothing. Avast Premium Security is a paid plan. A package for one computer costs $38.99 for the first year and $75.99 for every subsequent year. Avast Ultimate is also a paid plan and starts at $107.99/year, but you pay $69.99 for the first year.