How do assign a role to user after add to cart in ubercart in drupal 7? I am using ubercart for my site.. I need to assign a role to user after shopping with price base.. If user does $300 shopping then role 10%-role . if user does $400 shopping then 20%-role etc.. And remember these role next shopping.
Try to do this using Rules.


Add a new rule on event complete checkout.
Give your required conditions.
Add Assign role to user as action.


For your scenario you can do it using multiple rules.

Hope this will help you.