Per Diem Calculator
Calculate per diem travel allowances using GSA rates for lodging and meals & incidental expenses.
Results
Visualization
How It Works
The Per Diem Calculator helps you determine the total travel allowance reimbursement you're entitled to receive based on GSA (General Services Administration) daily rates for lodging and meals & incidental expenses. This calculator is essential for employees, contractors, and organizations to ensure accurate reimbursement that complies with federal per diem standards and avoids both underpayment and overpayment situations.
The Formula
Variables
- Daily Lodging Rate — The GSA-approved maximum daily hotel or accommodation allowance for your destination city, set by the federal government and updated quarterly based on location
- Daily M&IE Rate — The Meals and Incidental Expenses daily allowance set by the GSA, covering breakfast, lunch, dinner, and tips (typically 50% of this rate applies to partial travel days)
- Number of Travel Days — The total calendar days of your business trip, including both the departure and return days
- First/Last Day M&IE % — The percentage of the daily M&IE rate allowed on partial travel days (typically 75% for the first day and 75% for the last day, depending on meal expenses incurred)
- Similar Trips Per Year — How many times per year you take comparable trips to the same or similar destinations, used to project annual per diem totals for budgeting purposes
Worked Example
Let's say you're a consultant traveling to Denver for a 4-day client engagement. The GSA daily lodging rate for Denver is $145, and the daily M&IE rate is $68. On your first day, you'll arrive at 2 PM (so you only need dinner), and on your last day, you'll depart at 9 AM (so you'll have breakfast and lunch). You typically make this same trip to Denver about 6 times per year. For lodging, you calculate 4 days × $145 = $580. For meals, the first day counts as 75% of $68 = $51, the middle two days are full days at $68 each = $136, and the last day is 75% of $68 = $51, giving you $238 in M&IE. Your total per diem for this single trip is $580 + $238 = $818. Since you make this trip 6 times yearly, your annual per diem projection is $818 × 6 = $4,908.
Practical Tips
- Check the GSA per diem rates for your specific destination before your trip, as rates vary significantly by city and are updated quarterly—a hotel in Manhattan costs far more than one in rural Kansas, and the GSA rates reflect this difference
- Understand the partial day rule: if you travel on a partial day (arriving late or departing early), you typically receive only 75% of the M&IE rate for that day, so don't assume you get a full daily allowance unless you're there for breakfast, lunch, and dinner
- Keep detailed records of your actual travel dates and meal expenses, especially for partial days, because some employers require documentation to match per diem payments against actual receipts
- Use the annual trips multiplier feature to forecast your per diem budget if you travel frequently—this helps with personal financial planning and allows you to understand your true compensation when comparing job offers
- Remember that per diem is a reimbursement allowance, not a profit opportunity; you should only claim the rates that match your destination's GSA tier, even if you could have spent less on accommodations
Frequently Asked Questions
What is the difference between GSA per diem rates and what my company actually pays?
GSA rates are federal maximums set by the General Services Administration and are used by most government agencies and many private companies as their reimbursement standard. Your company may pay less than GSA rates to control costs, or in rare cases more (for executive travel), but most organizations align with GSA to ensure tax-compliant reimbursements. Check your employee handbook or travel policy to confirm your company's specific per diem rates.
Are per diem payments taxable income?
Per diem payments that do not exceed the GSA rates are generally non-taxable to the employee and not deductible by the employer, as long as the employee is in travel status away from their home or tax home. However, if you receive per diem in excess of GSA rates, the overage is taxable income. Always consult your company's payroll or tax department about how your specific per diem arrangement is treated.
What counts as a travel day for per diem purposes?
A travel day is any calendar day on which you are away from your home or tax home for business purposes, including the departure day and return day. For example, if you leave Monday morning and return Thursday evening, all four days (Monday through Thursday) typically count as travel days, though the Thursday M&IE rate may be reduced if you depart early enough that you skip some meals.
Can I choose to use actual expenses instead of per diem?
Some employers allow you to submit actual meal and lodging receipts for reimbursement instead of using the per diem allowance, which may be beneficial if your actual costs were lower than the GSA allowance. However, this varies by employer policy and may complicate tax treatment. Discuss this option with your accounting or HR department before choosing one method over the other, as you typically cannot mix methods on a single trip.
How do I find the correct GSA rates for my destination?
Visit the official GSA Meals and Incidental Expenses (M&IE) and Lodging Rates website, which provides city-by-city rates updated quarterly. Rates are organized by state and city, so search for your destination's county to find the correct tier. If your destination is not listed, use the rate for the nearest city or the default state rate.
Sources
- GSA Meals and Incidental Expenses (M&IE) and Lodging Rates
- IRS Publication 463: Travel, Gift, and Car Expenses
- U.S. Office of Personnel Management (OPM): Per Diem, Travel and Transportation Allowance Committee