How FAR Per Diem Rules Work
FAR 31.205-46 generally limits allowable lodging, meals, and incidental expenses to the maximum applicable per diem rates in effect at the time of travel. The applicable rate source depends on the travel location. The regulation references the Federal Travel Regulation for the contiguous United States, Joint Travel Regulations for specified U.S. areas, and Department of State regulations for foreign areas.
The process starts by identifying the travel destination and applicable rate for the date of travel. The contractor then compares the employee's qualifying expense or reimbursement amount with the applicable maximum and evaluates whether any special circumstances support a higher actual expense.
- Destination: Establishes which government travel-rate framework applies.
- Travel date: Determines the applicable rate in effect when the trip occurred.
- Expense category: Separates lodging, meals, and incidental expenses for appropriate treatment.
- Documentation: Supports the date, location, purpose, and traveler information.
- Approval: Provides evidence for exceptions and higher actual-expense treatment where applicable.
Maximum Per Diem Rates and Exceptions
Standard per diem treatment generally uses the maximum applicable rates. FAR 31.205-46 also provides for special or unusual situations in which actual costs above the referenced maximum may be allowable, subject to specified conditions. The higher amount cannot simply be accepted because the employee incurred the expense.
For a higher actual expense to qualify, the applicable government travel regulations must support use of the actual-expense method, a contractor officer or designee must approve written justification, and repeated or continuing use of the authority in a particular area requires advance contracting officer approval. Supporting documentation must be retained, including receipts for each expenditure of $75.00 or more under the applicable provision.
Partial travel days and trips where no lodging cost is incurred also require attention. FAR 31.205-46 states that the maximum daily rate generally would not represent a reasonable charge in these circumstances, so an appropriate downward adjustment is normally required.
Documentation and Per Diem Verification
FAR per diem compliance depends heavily on maintaining records that connect the expense with legitimate business travel. Required documentation includes the date and place of the expense, the purpose of the trip, and the name and title or relationship to the contractor of the person traveling.
Per Diem Verification provides a useful finance workflow for checking travel records against applicable rates, dates, destinations, expense categories, and supporting documentation. A structured verification process can identify records requiring additional review before reimbursement or contract cost reporting.
Organizations should also distinguish between standard-rate transactions and exception transactions. Keeping these categories visible makes it easier for finance teams to demonstrate why a particular amount was reimbursed and which approval supported the treatment.
Per Diem Policy and Internal Controls
Per Diem Compliance describes the broader control framework for ensuring that per diem transactions satisfy applicable requirements and support audit, risk, and control workflows. Internal controls should establish who may approve travel, which documentation employees must submit, how exceptions are handled, and how records are retained.
Per Diem Policy Compliance focuses on applying an organization's established travel rules consistently alongside applicable FAR requirements. A strong policy can define approved booking practices, reimbursement categories, rate limits, partial-day treatment, receipt requirements, and escalation procedures.
Finance teams can use approval workflows and exception reporting to separate routine transactions from records requiring additional review. This creates a consistent path from employee expense submission to reimbursement and contract accounting.
Per Diem Compliance and Procurement Workflows
Travel spending can intersect with procurement when contractors use approved suppliers, booking channels, purchasing controls, or authorization procedures for transportation and lodging. Connecting travel approvals with procurement controls can improve spend visibility and reinforce consistent authorization.
Related purchasing workflows may also benefit from structured validation. For example, finance teams can review requisitions, purchase orders, supplier information, and approvals alongside travel-related transactions when project costs need to be reconciled across multiple spending categories.
Tax considerations may also arise in broader expense workflows. tax compliance requires appropriate attention to jurisdiction rules, exemptions, taxable amounts, and documentation where applicable, while sales tax and use tax processes may apply to particular purchases associated with business travel.
Finance Automation and Audit Controls
Structured finance workflows can support per diem compliance by comparing submitted amounts with approved rates, routing exceptions, retaining approval histories, and connecting approved expenses with accounting records.
sales tax verification can use AI verification to identify anomalies, nexus triggers, and tax classification gaps in sales-tax processes. Although sales-tax verification and per diem review address different compliance areas, both demonstrate the value of systematic transaction validation.
Payment Processing By ACH can support ACH payments through automated file generation, bank-specific format compliance, access controls, and audit trails. For approved employee reimbursements or related payment workflows, these controls can provide structured authorization and transaction records.
Economic Nexus Threshold workflows can help identify when economic nexus thresholds are crossed and apply use tax through invoice matching and accounting entries. Separately, Notifications For Sales Tax Verification can monitor invoice matching and send alerts for sales-tax discrepancies, supporting accurate journal entries and compliance.
Accrual processes can also require detailed evidence. Audit Trails For Accruals documents steps in the accrual process, including automation and approvals, to support audit and compliance needs. The same audit-oriented principle is useful when maintaining evidence for per diem exceptions and travel-cost reviews.
Best Practices for Per Diem Compliance FAR
Contractors can strengthen per diem compliance by maintaining current rate information, standardizing travel approvals, documenting business purpose, and reviewing exceptions before costs are included in contract-related reporting.
- Match each trip to the applicable destination and travel date.
- Separate lodging, meals, and incidental expenses for accurate review.
- Document the business purpose and traveler information for each expense.
- Apply appropriate downward adjustments for partial travel days and qualifying circumstances.
- Retain written justification and approvals for higher actual expenses.
- Reconcile approved travel records with accounting and contract-cost data.
Summary
Per Diem Compliance FAR provides a structured approach to determining whether contractor lodging, meals, and incidental travel expenses satisfy FAR requirements. Effective compliance combines applicable government rates, documented business purpose, appropriate approvals, exception controls, and complete supporting records. Integrating these practices with finance, procurement, payment, tax, and audit workflows helps contractors maintain reliable travel-cost records and support accurate contract financial reporting.