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

Complete
Ireland → Sylhet District, Sylhet, BD
Item Name Destination Amount Conditions
Incidentals Chittagong, Bangladesh 10 EUR per day Actual-cost destination (Note 1, Circular 07/2017): the overnight rate is the vouched cost of accommodation and three meals, the ten-hour rate is the vouched cost of two meals and the five-hour rate is the vouched cost of one meal, in each case plus this incidental expenses allowance of EUR 10 per day.
Meal & Lodging Dhaka, Bangladesh 3753.5 BDT per night Paid in addition to the vouched cost of bed and breakfast, reimbursed at vouched actual cost per Appendix 2 of Circular 07/2017 (destination-specific accommodation figure carried in that appendix, not repeated here); the amount shown is the supplement covering remaining meals and expenses for a 24-hour absence abroad on official business.
Vouched Accommodation (VA) Rate Dhaka, Bangladesh 5630.25 BDT per night Vouched Accommodation (VA) rate: paid in addition to the vouched cost of accommodation. Per Note 2 of Circular 07/2017 the VA rate should not be routinely used except for travel to Brussels, where the vouched cost of room plus the VA rate applies to all officers on overnight visits.
Daily allowance Dhaka, Bangladesh 3753.5 BDT per day Ten-hour rate: applies to an absence abroad of ten hours or more without an overnight stay.
Daily allowance Dhaka, Bangladesh 1876.75 BDT per day Five-hour rate: applies to an absence abroad of between five and ten hours.

Source URL:
https://www.revenue.ie/en/employing-people/documents/dper-circular-07-2017-subsistence-allowances-abroad.pdf
This source provides official travel rate information from revenue.ie.