Per Diem Calculator: Daily Rate From Total Allowance
Work out the daily per diem rate from a total business travel allowance — the figure to compare against published government and company rates.
Adjust the inputs and select Calculate for a full breakdown.
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | Per diem rate |
|---|---|
| $2,000 / 10 days | $200.00 |
| $600 / 4 days | $150.00 |
| $15,000 / 60 days | $250.00 |
| $180 / 3 days | $60.00 |
How This Calculator Works
Enter the total travel allowance and the number of travel days. The calculator divides one by the other to give the per diem rate. Many policies pay 75% of the rate on the first and last day; the calculator gives the average daily figure across the full trip.
The Formula
Cost per Unit
Total Amount is the full cost or price, Quantity is the number of units it covers
Worked Example
A $2,000 allowance across 10 travel days works out to $200 a day. US GSA standard meals and incidentals rates run $59 to $79 a day for most cities; lodging is reimbursed separately, often $96 to $300 depending on city — higher in DC, NYC, San Francisco, and seasonal markets.
Key Insight
Per diem is one of the few business travel expenses that benefits from spending less than the cap — many policies let you keep the unspent portion as personal cash, taxable as income. The opposite trap is going over the rate and submitting an expense report instead; receipts and management approvals usually slow reimbursement significantly.
GSA per diem structure (FY 2025)
STANDARD CONUS RATE 2024-2025.
Lodging. $107/night standard CONUS (Continental U.S.).
M&IE. $68/day standard.
Substantial — applies to most U.S. counties not specifically rated.
NON-STANDARD AREAS (NSAs).
Higher rates for high-cost metros.
NYC Manhattan. Lodging $258-$334, M&IE $79-$92.
DC. Lodging $237-$334, M&IE $86-$92.
SF. Lodging $244-$295, M&IE $79-$86.
Boston. Lodging $221-$293, M&IE $79-$86.
LA. Lodging $182-$266.
Substantial — verify by zip code/county at GSA.gov.
SEASONAL RATES.
Some areas substantial — e.g., Aspen, Vail (winter), Cape Cod (summer).
Verify month-by-month.
FIRST/LAST DAY of travel.
M&IE reduced to 75%.
Substantial. $68 standard → $51 first/last day.
INCIDENTAL EXPENSES.
Substantial — included in M&IE (~$5/day).
Covers tips, fees.
Substantial — not separately reimbursable.
LODGING RECEIPT typically required.
Substantial — actual lodging cost up to per diem; receipt for actual amount required.
If less than per diem, reimbursed actual.
If more, traveler absorbs (unless authorized exception).
FOREIGN PER DIEM.
State Department sets rates.
Substantial — by city, often higher than CONUS.
London. ~$540 lodging + ~$165 M&IE typical 2024.
Tokyo. ~$370 + $145.
Substantial — verify aoprals.state.gov.
Tax treatment and private-sector applications
FEDERAL TAX TREATMENT (IRS).
Substantial — per diem at or below federal GSA rate substantially non-taxable.
Above federal rate substantial — excess taxable to employee.
Substantial — Pub 463.
Substantial — accountable plan substantial.
ACCOUNTABLE PLAN (IRS).
Substantial — travel business connection, adequate accounting, return excess.
Substantial — meets these → non-taxable.
Fails → all reimbursement taxable.
FIXED VS ACTUAL.
FIXED per diem. Employer pays standard amount regardless.
Substantial simpler administration.
Substantial — savings if traveler spends less.
ACTUAL EXPENSE. Receipts required. Limited to GSA rates substantial.
Substantial — more accurate but admin burden.
M&IE per diem typically fixed.
Lodging often actual (up to rate cap).
PRIVATE-SECTOR.
Substantial — many employers use GSA rates substantial benchmark.
Substantial — some pay 100% GSA, some 75%, some custom.
Substantial — high-tech companies often above GSA.
Substantial — startup / lean orgs may pay below.
INTERNATIONAL TRAVEL.
Substantial — State Department rates substantial.
Foreign post differential substantial — for hardship locations.
Substantial 15-35% premium for difficult posts.
MILEAGE.
Substantial — IRS standard mileage 67¢/mile 2024.
Substantial — covers gas, depreciation, insurance, maintenance.
Substantial — alternative to actual auto expenses.
EXEMPTIONS / TAXATION.
Substantial — travel >1 year at same location substantial — not 'temporary'.
All per diem becomes substantial taxable income.
Substantial — 'tax home' rules complex.
EXTENDED travel substantial planning consideration.
ALTERNATIVE STRUCTURES.
Corporate housing. Substantial — typically reimbursed actual.
Long-term assignments. Substantial different rules.
Substantial — relocation benefits separate framework.
RECEIPTS.
Lodging substantial — required for actual reimbursement.
M&IE substantial — generally not required per diem (deemed substantiated).
Substantial — substantial >$75 transactions require receipt under IRS rules.
U.S. GSA per diem rates (FY 2025)
Reference federal per diem rates.
| Location / Type | Lodging | M&IE |
|---|---|---|
| CONUS standard | $107 | $68 |
| NYC Manhattan | $258-$334 | $79-$92 |
| Washington DC | $237-$334 | $86-$92 |
| San Francisco | $244-$295 | $79-$86 |
| Boston | $221-$293 | $79-$86 |
| Los Angeles | $182-$266 | $79-$86 |
| Chicago | $182-$257 | $79-$86 |
| First/last day M&IE | — | 75% of full |
| London (foreign) | ~$540 | ~$165 |
| Tokyo (foreign) | ~$370 | ~$145 |
| IRS mileage rate 2024 | — | 67¢/mile |
GSA rates set fiscal year (Oct 1). Non-standard areas (NSAs) have higher rates. Foreign rates via State Department. Per diem ≤ federal rate non-taxable under accountable plan. Excess taxable to employee. Travel >1 year at same location loses 'temporary' status — all per diem taxable. Lodging typically actual (receipts) up to cap; M&IE typically fixed per diem.
Frequently Asked Questions
What is per diem?
A fixed daily allowance covering travel-related expenses — typically meals and incidentals, sometimes lodging. It replaces individual receipt-by-receipt reimbursement with a flat daily rate.
How is per diem calculated?
Divide the total allowance by travel days. A $2,000 allowance across 10 days is a $200 daily per diem.
Is per diem taxable?
Generally no, if it stays within IRS-published rates and the company uses an accountable plan. Amounts above the published rate or paid without proper documentation can become taxable income.
Can I keep the unspent per diem?
Usually yes — that is the trade-off for accepting a flat rate. Some companies require unspent amounts to be returned; check the specific policy.
What if I spend more than the rate?
The overage is typically out of pocket unless you switch to expense reporting with receipts and approval. Per diem is meant to settle small variations without paperwork — large overruns usually need a different mechanism.
When is this calculator unreliable?
Less reliable when non-federal employer uses different rates (private sector often custom), when actual expense reimbursement vs per diem mix used, when high-cost locations need OCONUS State Department rate (foreign), when lodging tax + occupancy fees reimbursed separately above per diem, when state/local public-sector rates differ from federal GSA, or when IRS rate caps for non-taxable substitution exceeded (excess becomes taxable W-2 income). First/last day M&IE is 75% of standard.
References & Authoritative Sources
- U.S. General Services Administration (GSA) — Per Diem Rates · consulted June 1, 2026 · Federal travel authority
- U.S. State Department — Foreign Per Diem Rates · consulted June 1, 2026 · Federal foreign travel
- Internal Revenue Service (IRS) — Publication 463 — Travel, Gift, and Car Expenses · consulted June 1, 2026 · Federal tax authority
Related Calculators
Methodology & Review
Per diem = daily rate × days. Calculator returns total reimbursement. U.S. federal GSA per diem 2024-2025: lodging $107-$334/night (location-based); M&IE (Meals & Incidental Expenses) $59-$92/day; first/last day 75%. International rates set by State Department. Foreign service post differentials substantial. Tax treatment: under IRS rate = non-taxable; above = taxable. RELIABILITY: Reliable for GSA-based domestic federal travel. Less reliable when (a) non-federal employer uses different rates; (b) actual expense reimbursement vs per diem mix; (c) high-cost locations need OCONUS State Department rate; (d) lodging tax + occupancy fees may be reimbursed separately above lodging per diem; (e) state/local public-sector rates may differ; (f) IRS rate caps for non-taxable substitution.
Updated