As Per Labour Law, you are entitled to receive you gratuity when you leave / get terminated (for no criminal offense)from a company.

If working period is less than 5 years they are supposed to pay 1 month basic salary & no. of years worked. eg: if some one worked 5 years - 1 month basic salary X 5 times.

If more than 5 years, from sixth year they are supposed to pay 1.5 month basic from sixth year onwards.

Make sure you get your gratuity and not just be happy with extra month.

If you got your gratuity and extra one month salary, you company is generous.