Look up per diem reimbursement rates and mileage deductions for business travel worldwide.

Complete
United Kingdom → Tamil Nadu, India
Item Name Destination Amount Conditions
Meals Chennai (Madras), India 2203.5 INR per day Over 5 hours rate: covers subsistence expenses for a period of more than 5 but less than 10 hours, measured by reference to the times of arrival in and departure from the foreign country.
Meals Chennai (Madras), India 5097.5 INR per day Over 10 hours rate: covers subsistence expenses for a period of more than 10 but less than 24 hours, measured by reference to the times of arrival in and departure from the foreign country.
Meals and incidentals Chennai (Madras), India 5917 INR per day 24 hour rate: covers the total cost of meals and daily hotel-to-office travel for a full 24-hour period.; The actual room rate is paid in addition to this amount (source shows the rate as 'plus room rate').
Lodging Chennai (Madras), India 14540.5 INR per night No specific conditions
Breakfast Chennai (Madras), India 0 INR per meal This amount is included in the room rate, so it is not paid separately on top of the lodging rate.
Lunch Chennai (Madras), India 1843.5 INR per meal No specific conditions
Dinner Chennai (Madras), India 2534.5 INR per meal No specific conditions
Incidentals Chennai (Madras), India 305 INR per day Source row labelled 'Other': other expenses incurred during the day; employers may use the individual meal and other rates instead of the over 5 hour, over 10 hour and 24 hour rates.
Drinks Chennai (Madras), India 719.5 INR per day No specific conditions
Transport Chennai (Madras), India 514.5 INR per day Covers daily travel between the employee's hotel and office.
Total residual Chennai (Madras), India 5917 INR per day Total residual rate: intended to cover the total cost of meals in a period of 24 hours plus the cost of daily travel between the employee’s hotel and office; the 24 hour rate is the sum of the room rate and this total residual rate.

Source URL:
https://www.gov.uk/guidance/expenses-rates-for-employees-travelling-outside-the-uk
This source provides official travel rate information from gov.uk.