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

Complete
United Kingdom → Port Au Prince, Ouest, HT
Item Name Destination Amount Conditions
Meals Port au Prince, Haiti 19.5 USD 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 Port au Prince, Haiti 48.5 USD 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 Port au Prince, Haiti 67.5 USD 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 Port au Prince, Haiti 132.5 USD per night No specific conditions
Breakfast Port au Prince, Haiti 10.5 USD per meal No specific conditions
Lunch Port au Prince, Haiti 18 USD per meal No specific conditions
Dinner Port au Prince, Haiti 28 USD per meal No specific conditions
Incidentals Port au Prince, Haiti 0 USD 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 Port au Prince, Haiti 2.5 USD per day No specific conditions
Transport Port au Prince, Haiti 8.5 USD per day Covers daily travel between the employee's hotel and office.
Total residual Port au Prince, Haiti 67.5 USD 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.