Per Diem / Daily Allowance Calculator

Three simple steps: (1) Select your rate standard - GSA (US rates), UK HMRC rates, or Custom. (2) Choose your destination from the dropdown - the calculator shows the daily lodging and M&IE rates for each location. (3) Enter your trip duration in days using the preset buttons or type a custom number. The calculator instantly shows your daily breakdown, total per diem for the trip, tax implications, and a full rate reference table. Toggle the actual expense comparison to see per diem vs actual cost side by side.

The calculator includes GSA CONUS per diem rates for FY 2025 covering 24 US locations: the CONUS standard rate ($176/day), plus major cities including New York City ($401/day), Washington D.C. ($372/day), San Francisco ($383/day), Los Angeles ($341/day), Chicago ($329/day), Boston ($373/day), Miami ($305/day), Seattle ($325/day), Denver ($317/day), Atlanta ($290/day), Dallas ($274/day), Phoenix ($269/day), Houston ($267/day), Orlando ($269/day), Las Vegas ($269/day), Philadelphia ($305/day), Minneapolis ($290/day), Detroit ($262/day), Portland ($305/day), San Diego ($341/day), Nashville ($290/day), Austin ($290/day), and Honolulu ($393/day - non-foreign OCONUS).

The calculator includes UK HMRC benchmark subsistence rates for: Central London (£200/day total - £150 lodging + £50 M&IE), UK Standard Rate (£135/day - £100 lodging + £35 M&IE), and UK Other Locations (£120/day - £85 lodging + £35 M&IE). The M&IE rates cover breakfast (approximately £10), lunch (£12), dinner (£25), and incidentals (£5) per the HMRC benchmark guidance.

Per diem allowances paid at or below the published GSA or HMRC rates are generally considered nontaxable reimbursements. They do not need to be reported as employee income on W-2 forms (US) or through payroll (UK). However, any per diem payments above the published rates may be considered taxable income. Additionally, per diem for travel that is not considered "business travel" (e.g., commuting to a regular workplace) may be taxable. Our calculator clearly shows the nontaxable amount and provides simplified tax guidance - consult a tax professional for your specific situation.

Per diem reimbursement pays a fixed daily rate regardless of actual costs - if your hotel costs less than the per diem rate, you keep the difference. Actual expense reimbursement requires submitting receipts and being reimbursed for exactly what you spent. Per diem is simpler administratively (no receipts needed for amounts under the rate) and can incentivize cost savings. Actual reimbursement may be better when costs are unpredictable or significantly exceed standard rates. Our calculator shows a side-by-side comparison so you can see which method is more beneficial.

Absolutely. This per diem calculator runs 100% locally in your browser. Your destination selections, trip durations, expense amounts, and all travel data are never sent to any server, stored in a database, or tracked in any way. All calculations happen locally on your device - nothing leaves your computer. No signup or account needed.

Yes - the per diem / daily allowance calculator is 100% free with no signup, no account, and no usage limits. Calculate per diem for any destination, any trip duration, and any rate standard as many times as you need. Model different scenarios - compare rates across multiple cities, try different trip lengths, or compare per diem vs actual expenses. There are no hidden charges, premium tiers, or usage caps.