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

Complete
United Kingdom → Madrid, Spain
Item Name Destination Amount Conditions
Meals Madrid, Spain 32 EUR 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 Madrid, Spain 86 EUR 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 Madrid, Spain 114.5 EUR 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 Madrid, Spain 172.5 EUR per night No specific conditions
Breakfast Madrid, Spain 23 EUR per meal No specific conditions
Lunch Madrid, Spain 29.5 EUR per meal No specific conditions
Dinner Madrid, Spain 51.5 EUR per meal No specific conditions
Incidentals Madrid, Spain 0 EUR 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 Madrid, Spain 5 EUR per day No specific conditions
Transport Madrid, Spain 5.5 EUR per day Covers daily travel between the employee's hotel and office.
Total residual Madrid, Spain 114.5 EUR 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.