Per diem and mileage calculator for a whole trip

GSA does not publish one hotel figure per city: it publishes twelve, one per month of the federal fiscal year, and seasonal areas swing hard. Jackson / Pinedale, Wyoming runs from $215 to $441, and beach and ski towns do the same in the other direction. The calculator takes each night separately, so a stay from September 29 to October 2 counts two nights at the FY2026 rate and one at FY2027. If the room cost less than the maximum, type the price: you are paid what you spent, never more than the cap. Lodging taxes are not in the maximum and are reimbursed apart, which is why they have their own field.

The rate lookup shows the twelve months of any area, and each state page lists every area of the state with its FY2026 and FY2027 figures side by side.

Two calendars cross in a business trip. The federal fiscal year turns on October 1, and with it the lodging table. The IRS calendar year carried a second break in 2026: on July 1 the business rate went from 72.5 cents to 76 cents a mile. Most calculators keep one rate for the whole trip. Here every day reads its own table, every night its own month, and the mileage line uses the rate of the departure date (the mileage reimbursement calculator splits a year of miles around July 1).

That is the data advantage of the site: 301 GSA records with twelve monthly lodging figures for two fiscal years, 40,426 ZIP codes, and 2,387 cities of 15,000 people or more matched to their county by Census files, so that typing "Lancaster, CA" or "93534" finds the Los Angeles area rate instead of the standard one.

Each GSA area has one of five M&IE rates, from $68 to $92. On the day you leave and the day you come back, you receive 75% of it, whatever the hours; the days in between are paid in full. A trip that starts and ends on the same day pays 75% if it lasts more than 12 hours, nothing otherwise.

When the government or a conference fee pays a meal, its value comes off: at $80 M&IE a lunch is worth $22, a dinner $33. On a 75% day the full value comes off the reduced amount, and no day falls below the $5 of incidental expenses. An airline snack or a free hotel breakfast is not deducted. The M&IE page shows the breakdown of every tier.

For a federal employee these rates are the law of the trip: the agency pays lodging up to the cap and M&IE at the rate, following the travel authorization. A private employer is free to pay less, more or its own flat amount; what the federal rates decide for it is the tax side. Under an accountable plan, per diem up to the federal rate and mileage up to the IRS rate need no receipts for the amount and stay off the W-2, and anything above is wages unless it is returned (IRS Publication 463). The travel reimbursement page computes that excess.

A self-employed person deducts business travel on Schedule C and may use the M&IE rate instead of meal receipts, with the meal part limited to 50% (80% for drivers under Department of Transportation hours of service, see the truck driver page). Lodging always needs receipts.

It covers the 48 contiguous states and the District of Columbia, the area GSA calls CONUS. Alaska, Hawaii and the territories are set by the Department of Defense and foreign cities by the Department of State; the OCONUS page computes a trip from the rates you read there. It does not apply the actual expense method, which can reach 300% of the per diem when an agency approves it, nor the reduced rates some agencies set for long stays. It cannot know your employer's policy. And it never sends what you type anywhere: the arithmetic runs in this page, which is why the share link carries your inputs in its address.

Lodging and M&IE come from the GSA per diem files (FY2027 ZIP file published September 3, 2026), meal values from the GSA breakdown, the day rules from the Federal Travel Regulation, mileage from the IRS and GSA POV pages, fuel and electricity prices from the EIA, vehicle consumption from the EPA. GSA publishes the next fiscal year in August or September, the IRS its mileage rates in December (and in 2026, a second time in June). The method page lists every rule with the test cases that check it.