Tipping
The Tipping settings screen lets you configure tip amounts and presets that are presented to customers during processing.
By default, Tipping percentages are 15%, 20%, and 25%.
Custom Tips
Custom tips are always allowed when Tipping is presented.
Whether tipping is offered during a transaction is controlled by your Payment Flow — set the Tipping option to Ask to present a tip screen, or Never to skip it entirely.

Tip set to 'Ask' during processing