Travel Per Diem Calculator

Business-travel allowances usually separate lodging from meals and incidental expenses (M&IE). Lodging follows nights away and may depend on receipts or a nightly ceiling. M&IE follows travel days, with a reduced allowance often applied to departure and return dates. A five-day trip normally contains five M&IE dates but only four lodging nights.

The rate belongs to a policy, destination, and travel period. U.S. federal travel within the continental United States uses General Services Administration locality rates, while non-foreign and foreign destinations use other authorities. Employers and contracts may adopt those tables, apply a percentage, or define their own reimbursement rules. Recording the rate source beside the trip is therefore as important as calculating the total.

Full M&IE day

A calendar day eligible for the full meals-and-incidentals rate under the chosen policy.

Travel day

A departure, return, or same-day travel date that may receive a reduced percentage.

Provided meal

A meal furnished by an eligible source that the governing policy says must be deducted.

Lodging cap

The nightly allowance multiplied by reimbursable nights; actual-receipt policies may pay less.

Meal deductions and lodging treatment are policy decisions, not universal arithmetic. A conference breakfast, hotel breakfast, airline meal, receipt above a cap, or interrupted overnight stay can be treated differently by different rules. A reliable estimate keeps these choices visible instead of hiding them inside one daily rate.

How to Use This Tool:

Choose and verify the policy inputs before entering expenses; the calculator does not look up a destination rate.

1. Enter a Destination or rate source and the departure and return dates. Dates are counted as inclusive UTC calendar dates, and the trip may span no more than 366 days.
2. Select a Policy profile and M&IE tier, then confirm the full-day rate and meal breakdown against the authority or employer policy for that destination and date.
3. Choose the Lodging basis. Use the nightly allowance, capped actual receipts, uncapped actual receipts, or no lodging as the policy requires. Override lodging nights only when the trip record supports a different count.
4. List provided meals one date or trip-day number per line, followed by a colon and breakfast, lunch, or dinner. Correct any line that does not match the trip dates or recognized meal names.
5. Review the daily schedule, especially reduced travel days, meal deductions, and reimbursable lodging. Keep the rate-source label with the result for approval or audit.

Interpreting Results:

The allowance total combines Net M&IE and Lodging total. Read the daily rows before relying on the sum: the first and last dates may be prorated, a provided meal can reduce only the date on which it appears, and lodging normally ends before the return date.

A cap is not evidence that an expense is reimbursable. In capped-actual mode, receipts above the cap are excluded; in uncapped mode they remain in the estimate but may still fail the governing policy. The currency label formats the entered amounts and does not perform exchange-rate conversion.

Technical Details:

The calculation builds one row for every inclusive calendar date. Each row receives either the full M&IE rate or the selected first-and-last-day fraction. Recognized meal deductions are applied only when the selected scope permits them, and an optional incidentals floor prevents deductions from reducing that day's M&IE below its prorated incidentals component.

Formula Core:

For day d, the policy multiplier is applied to rates and meal components before daily proration and deductions.

Lookup and Rule Core:

The FY 2026 CONUS presets pair each full-day M&IE tier with the official meal components used for deductions.

Lodging payment is zero when lodging is excluded, C for the nightly-allowance basis, the lesser of receipts and C for capped actuals, or the full entered receipts for uncapped actuals. Provided-meal lines accept an ISO date or a 1-based trip-day number and deduplicate repeated meal names on the same date.

Policy and Accuracy Notes:

This is an estimate from the rates and policy choices entered. It does not decide reimbursement eligibility, tax treatment, or whether a particular meal or lodging charge is allowable.

• Verify the destination, fiscal year, locality, M&IE breakdown, and first/last-day rule with the current authority.
• Check employer or agency rules for provided meals, receipt requirements, actual-expense approval, lodging taxes, and exceptions.
• Use the daily schedule for audit; a plausible grand total can still hide a wrong date, meal, or night count.

Worked Examples:

References:

• Federal Travel Regulation and related files, U.S. General Services Administration, updated January 16, 2026.
• M&IE breakdowns, U.S. General Services Administration, updated July 31, 2026.
• Per diem rates, U.S. General Services Administration.