Gratuity exemption: least of three test determines exempt portion for noncovered employers; excess gratuity is taxable.
Gratuity from a noncovered employer is exempt to the extent of the least of three amounts: the service based fraction computed from the average monthly salary (which includes basic pay, one month's dearness allowance, and average monthly commission), the statutory monetary ceiling, and the gratuity actually received; any excess over that exempt amount is taxable.

Gratuity exemption: part determined by 15 days salary times completed years, excess treated as taxable salary.
Gratuity exemption is determined by taking the least of: the product of 15 days' salary and completed years of service, the statutory ceiling, and the gratuity received. Completed years may be rounded to include qualifying months. The exempt portion is that least amount; any excess over the exempt amount is taxable as salary income in the assessment year.

Gratuity exemption under Section 10(10)(i) remains available even if retiree accepts private sector employment after retirement.
Gratuity paid to a government employee on retirement is fully exempt from income tax under the governing gratuity exemption provision, and that exemption remains available even if the retiree subsequently accepts employment in the private sector.