GSA M&IE Per Diem Explained

What M&IE covers (and what it does not)

M&IE is the daily allowance for meals and incidental expenses on official travel. GSA publishes CONUS tier totals plus a breakdown into breakfast, lunch, dinner, and incidental expenses. Incidental expenses typically cover items like tips to hotel staff and similar small costs defined in federal travel guidance.

Lodging is excluded. Hotel caps vary by destination and fiscal year. You must use GSA’s lodging rate lookup for overnight stays. Combining M&IE math with a hotel number you guessed from memory will under- or over-state a trip budget. The GSA M&IE Per Diem Calculator intentionally models meals and incidentals only so the total stays honest about its scope.

M&IE tiers in the calculator

GSA sets multiple CONUS M&IE tiers ($68, $74, $80, $86, and $92 in the verified HustleNumbers table). The $68 tier is standard CONUS; higher tiers apply to designated non-standard areas. Your destination’s tier comes from gsa.gov’s per-diem search for the travel dates, not from a generic “default” unless your agency allows that fallback.

Each tier row includes the full-day total and the published 75% first/last-day amount GSA lists for that tier. The calculator applies those published values; it does not recompute 75% from breakfast and lunch components separately.

Why first and last days are 75%

Federal Travel Regulation 301-11.18 limits M&IE on the first and last calendar days of travel to 75% of the full tier rate. Travelers often depart late or return early, so the rule assumes partial-day meal patterns on those boundary days.

The calculator treats up to two days at the 75% rate: one for the first calendar day and one for the last when the trip spans more than one day. Middle days bill at 100%. A one-day trip uses a single day at 75% only (one travel day, zero full days). A two-day trip uses two days at 75%. A five-day trip uses two days at 75% and three full days at 100%.

Counting travel days vs hotel nights

Enter calendar travel days, not hotel nights. A common pattern: fly out Monday morning, work through Thursday, fly home Friday afternoon. That is five travel days even if you booked four hotel nights (Monday through Thursday).

Miscounting nights instead of days is the fastest way to mis-state M&IE. When in doubt, list each calendar date you are in travel status and count the rows.

How to run a total in the tool

1. Look up your destination on gsa.gov and note the M&IE tier for your travel month.
2. Open the GSA M&IE Per Diem Calculator.
3. Select the matching tier (Standard CONUS $68 if that is what GSA shows).
4. Enter total calendar travel days.
5. Read total M&IE, full-day count, 75% travel-day count, and the breakfast/lunch/dinner/incidental breakdown.
6. Check the verification date and GSA source link on the results panel.

Worked example (Standard $68 tier, 5 travel days)

This matches the HustleNumbers calculator logic today. Agency policy, taxes, and actual receipts can change what you may claim.

Inputs: $68 tier, 5 calendar travel days.

Day split: 3 full days at $68.00; 2 travel days at $51.00 (GSA’s published 75% value for the $68 tier).

Math: (3 × $68.00) + (2 × $51.00) = $204.00 + $102.00 = $306.00 total M&IE.

Lodging for four hotel nights is calculated separately on gsa.gov. Do not add hotel caps into this $306.00 figure.

What this calculator excludes

Lodging per diem, international rates, actual-expense reimbursement, conference fees, mileage, and agency-specific overrides are out of scope. OCONUS destinations use different tables. If your finance office applies local policy (for example, no reimbursement on leave days), follow agency guidance over a generic web total.

Common mistakes

• Adding hotel limits to an M&IE total as if they were one number.
• Using hotel-night counts instead of calendar travel days.
• Applying 100% to every day including departure and return.
• Picking a tier from the wrong city or fiscal year on gsa.gov.
• Treating this web total as binding agency authorization without finance review.