Per diem is a Latin term meaning "per day," used to describe a fixed daily allowance paid to employees for travel-related expenses such as meals, lodging, and incidental costs. It serves as a simplified method for reimbursing workers on business trips without requiring itemized receipts.
The U.S. Internal Revenue Service (IRS) sets standard per diem rates annually for federal employees and contractors. These rates vary by location and are updated each year based on regional cost-of-living differences. For example, in 2023, the IRS established a $100 daily rate for most domestic destinations, with higher amounts-up to $260-for high-cost areas like New York City and San Francisco.
Employers use per diem payments to cover the cost of meals and incidental expenses during business travel. The amount is typically paid to regular wages and may be tax-free if it meets IRS guidelines. This system reduces administrative burden because employees don't need to submit detailed expense reports for small daily costs.
When an employee travels for work, their employer may provide a per diem allowance instead of reimbursing actual meal or lodging costs. The payment is usually issued as a flat daily rate regardless of the actual amount spent. This simplifies accounting and ensures consistency across travel assignments.
For instance, a sales representative traveling from Chicago to Los Angeles for a three-day client meeting receives a per diem of $125 per day. They spend $110 on meals and $15 on incidentals. The employer pays $375 total ($125 × 3 days), and the employee keeps the difference. No receipts are required because the rate covers typical daily spending.
If the employee spends more than the per diem rate, they must cover the excess out of pocket. If they spend less, they do not receive a refund unless the company policy allows it. This structure prevents abuse while maintaining fairness.
Per diem arrangements fall into two categories: standard and actual expense-based. Standard per diem uses IRS-set rates and is common in government contracts and large corporations. Actual expense-based per diem requires documentation of actual costs and is less frequently used due to administrative overhead.
| Type | Rate Basis | Receipts Required? | Best For |
|---|---|---|---|
| Standard Per Diem | IRS-defined rates by city | No | Regular business travel, government contracts |
| Actual Expense-Based | Employee's documented spending | Yes | High-value travel, audit-sensitive environments |
Some industries rely heavily on per diem. Construction workers on temporary site assignments, military personnel deployed overseas, and journalists covering breaking news often receive per diem payments. In these cases, the allowance helps maintain morale and supports basic living costs during extended absences from home.
A non-obvious fact: The IRS does not require employers to pay per diem at the full standard rate. Employers may offer lower amounts, but any shortfall must be reported as taxable income. For example, if the IRS rate is $150 per day but the company pays only $100, the $50 difference is treated as wages and subject to payroll taxes.
Per diem is often confused with salary or overtime pay. It is neither. Per diem is a reimbursement for temporary, daily expenses incurred during travel. It is not a form of compensation for time worked.
Another misconception is that per diem applies only to international travel. While foreign travel rates differ -such as $280 per day in Tokyo-the concept applies equally to domestic trips. The IRS provides separate tables for domestic and foreign locations, but both follow the same principle: daily allowances based on geographic cost levels.
Some employees assume they can claim per diem as a personal deduction. That is incorrect. Individuals cannot deduct per diem on their personal tax returns unless they are self-employed and meet strict criteria under IRS Publication 463. Even then, the deduction is limited to business-related travel and requires detailed records.
Consider a marketing manager from Seattle assigned to lead a product launch in Miami. The trip lasts four days. The company's policy follows IRS guidelines, using the $130 per diem rate for Miami, which is above the national average due to higher lodging and dining costs.
On Day 1, the manager arrives late and eats dinner at a hotel restaurant, spending $45. On Day 2, they attend meetings and eat lunch at a café, spending $22. Day 3 includes a client dinner costing $78. Day 4 involves a morning flight home and a quick airport meal for $30.
Total actual spending: $175. Total per diem received: $520 ($130 × 4 days). The employee keeps $345 in unused funds. No receipts are needed because the per diem exceeds actual costs. The employer treats the entire $520 as a tax-free expense reimbursement.
This example shows how per diem streamlines travel accounting. Without it, the employee would have to collect and submit 15+ receipts, track mileage, and wait weeks for reimbursement. With per diem, the process takes minutes.
Proper handling of per diem affects both employee taxes and employer compliance. The IRS classifies per diem payments as non-taxable when they match or are below the standard rate. Excess payments are taxable income and must be included in the employee's W-2 form.
Employers must track per diem usage by location and duration. Failure to do so can trigger IRS audits. According to the IRS, businesses that fail to report per diem correctly face penalties of up to $10,000 per violation, especially in multi-state or international operations.
I once managed payroll for a logistics firm with 120 field agents. We switched from itemized reimbursements to standardized per diem rates. Processing time dropped from 14 days per employee to under 48 hours. Audit readiness improved dramatically because we used IRS-approved figures and eliminated receipt discrepancies.
Per diem remains a practical tool for managing business travel costs. It balances simplicity with compliance, ensuring employees are supported without creating recordkeeping burdens. When applied correctly, it benefits both individuals and organizations.