The best replacement for gratuity is tip.

The best alternatives to gratuity are rated as following:
★★★★★  tip
★★★★  service charge
★★  provident fund
★  tips
★  pf
  sgli
  service fee
  bribe
  tipping

Your alternative for gratuity is not listed? Suggest!
Speaking about gratuity, one probably shouldn't forget about new pension scheme.

Other search terms related to gratuity and their ratings are:
★★★★★ new pension scheme
★★★ ctc
You have in mind a companion for gratuity and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of gratuity in all years. Click on graph for more.
gratuity
tip
service charge