How Much of Your Business Trip Is Actually Deductible?
Business travel deductions hinge on the IRS "Away From Home" rule: your trip must take you away from your tax home long enough to require sleep or rest, generally meaning an overnight stay. Once that's met, the GSA (General Services Administration) publishes daily per diem ceilings for lodging and M&IE (meals & incidental expenses) by locality, which are commonly used as a reference cap for what's reasonably deductible. This calculator compares your actual lodging and meal spending to your trip's GSA rates, applies the mandatory 50% limitation on meal deductions under IRC Section 274(n), and treats transportation as fully deductible, giving you a total deductible amount alongside your total spending.
How It's Calculated
| Step | Item | Formula |
|---|---|---|
| 1 | Lodging deductible | min(actual lodging, GSA lodging rate) × nights |
| 2 | Meals deductible | 50% × min(actual meals, GSA M&IE rate) × nights |
| 3 | Transportation deductible | 100% of transportation cost |
| 4 | Total deductible | Lodging + meals + transportation |
GSA per diem rates vary by exact destination and update annually — check GSA.gov for the current lodging and M&IE rates for your trip's locality before finalizing an expense report.
Frequently Asked Questions
To deduct travel expenses, the IRS requires your trip to take you away from your tax home substantially longer than an ordinary workday and require sleep or rest to meet the demands of your work — generally an overnight stay. Day trips without an overnight stay don't qualify for lodging or meal per diem treatment (IRS Topic 511).
Under IRC Section 274(n), business meal expenses are generally limited to a 50% deduction, even when using the GSA per diem method for meals and incidental expenses (M&IE). Lodging and transportation costs don't carry this limitation.
The General Services Administration publishes daily lodging and M&IE (meals & incidental expenses) rate ceilings for every U.S. locality. Reimbursing at or below the GSA rate lets employers avoid requiring detailed receipts. Check GSA.gov for the current rate at your trip's destination.
※ Actual figures may vary by individual circumstances. This is a reference estimate only.