Per Diem Trip Cost Calculator

What Is the Per Diem Trip Cost Calculator?

This tool calculates daily per diem rate × number of days for a business trip. GSA per diem rates vary by destination city/county and by date, and change annually -- look up your exact rate at gsa.gov/travel/plan-book/per-diem-rates before using it here, since this tool doesn't have access to that full location-based lookup table.

How to Use This Tool

Enter your destination's daily per diem rate (from gsa.gov) and your trip's number of days. Your total per diem allowance appears instantly.

What the Result Represents

The calculator multiplies the daily rate by the number of trip days, with negative inputs treated as zero. With a hypothetical rate of 79 dollars a day over 5 days, the total is 395 dollars. The daily rate you type is your own figure, so the result is only as accurate as the rate you looked up. The tool does not fetch rates for you.

Counting Days Correctly

The most common mistake is miscounting days. A trip that starts Monday and ends Friday is five calendar days, but travel days often receive special treatment. Under federal travel rules, the first and last day of travel are commonly paid at 75 percent of the meals portion, though this varies by employer and situation; the tool does not apply any partial-day reductions. If your organization does, either enter a fractional number of days (for example 4.5) or run the tool once for full days and once for partial days with an adjusted rate, then add the results. Confirm your employer's policy in writing.

Worked Example: Two Locations

Imagine a trip with three days in one city at a hypothetical 74 dollars a day and two days in another at a hypothetical 92. Run the calculator twice: 74 x 3 = 222 and 92 x 2 = 184. The combined allowance is 406 dollars. Because rates differ by destination, splitting a multi-city trip this way is more accurate than averaging.

Lodging and Meals Are Different Things

Federal per diem has two components: lodging and meals and incidental expenses (M&IE). Depending on the policy, some organizations reimburse actual lodging up to the lodging limit and pay a flat M&IE amount, while others pay a single combined daily amount. Make sure the rate you type matches how your employer defines the allowance. If you enter only the M&IE rate, the total covers meals and incidentals, not hotel costs, and vice versa.

Limits and Cautions

• Rates vary by location and by date, and are revised each federal fiscal year. Always use the rate that applies to the dates of your travel.
• The tool does not account for meals provided at conferences or by the hotel, which policies often deduct from the allowance.
• It is not a tax calculator. Whether per diem reimbursements are taxable, and how they interact with an employee's or contractor's taxes, depends on the arrangement and on IRS rules. Check IRS guidance or consult a tax professional.
• Actual expenses can be lower or higher than the per diem, and some employers reimburse actual receipts instead.

Use the estimate for trip budgeting, expense report drafts, or quotes for clients; verify every number with the official source and your organization's travel policy before you rely on it.

Frequently Asked Questions