What per diem covers, and what it does not
Separate the room ceiling, the meal allowance and the other expenses on a travel claim.
The essentials
Worked example
How to calculate per diem for a trip, one day at a time
Turn the rates into a transparent estimate without confusing nights and travel days.
Meal allowances
First and last day of travel per diem: the 75% M&IE rule
Why travel-day meals are reduced, and how that affects a two-night trip.
Deducting provided meals without losing the incidental allowance
Which meals reduce M&IE, the order of the calculation, and why free hotel breakfast is different.
Per diem for travel without an overnight stay
Understand the federal more-than-12-hour threshold, calendar-day treatment and why a same-day trip is outside the overnight trip calculator.
Locations
Choose the right rate locality for the work address
Why county definitions and the work location matter more than the city in a hotel’s name.
What a ZIP lookup can—and cannot—tell you
Understand multiple matches, leading zeroes and the difference between a rate file and an address database.
Standard CONUS per diem rate: when it applies
Use the standard rate only after checking whether a named city or county has its own allowance.
Dates & editions
A trip that crosses October 1 uses two rate editions
Match each date to the federal fiscal year and avoid applying a new rate to an old night.
Read seasonal lodging rates before choosing travel dates
A single destination can have different room ceilings across the year. Use the month, not just the annual peak.
Room costs
Lodging taxes sit outside the CONUS room ceiling
Keep the base room rate, lodging taxes and meal taxes in their correct places.
An actual hotel price is different from a lodging ceiling
Budget accurately when the room is below the ceiling, above it, or provided without charge.
Government hotel rates and GSA per diem limits
A hotel’s government rate is a booking offer, while the GSA lodging figure is a reimbursement ceiling. Check eligibility, room charges and conditions separately.
Checking hotel tax exemptions before federal travel
Use official state information and the billing account type to check a hotel tax exemption. Keep state sales tax separate from local lodging taxes.
Weekly and monthly lodging on an extended trip
How a long-stay lodging bill differs from a normal nightly quote, and why a reduced federal per diem requires an agency determination.
Scope & policy
Using GSA rates as a contractor or private employer
A federal reference is useful for planning, but a contract or employer policy controls the actual arrangement.
CONUS vs OCONUS per diem: find the right rate source
The continental GSA directory does not cover every U.S. state or international destination.
Is per diem taxable? Accountable plans and the federal rate
When an employer’s per diem stays off your W-2 wages, when the excess becomes taxable, and which federal rate the IRS compares it with.
Working with data
Read, download and check the official rate data
Understand fiscal months, source rows, stable locality IDs and the difference between a snapshot and a live feed.
Planning
Compare travel allowances without mistaking them for hotel prices
Make comparisons on the same month, separate room and meal amounts, and account for your itinerary.
Claims & approval
Per diem receipts and travel claim documents
Which lodging and other receipts to retain, how meal allowances differ from actual expenses, and what to record before filing a federal travel claim.
When available hotels exceed the lodging rate
How actual expense authorization differs from the normal lodging ceiling, what to document and why the 300% limit is not automatic approval.
Weekends, leave and returning home during travel
Distinguish required nonworkday stays from personal leave and a return home. A calendar day in a trip does not by itself establish reimbursement.