Seven Mistakes Worth Avoiding
Some of these cost you money you were entitled to. Others create exposure you do not want. Both are worth ten minutes of attention.
1. Assuming you cannot claim it because you take the standard deduction
This is the single most expensive misunderstanding, and it causes reservists to skip the deduction entirely. The reservist travel deduction is an above-the-line adjustment on Schedule 1, line 12. It is available whether or not you itemize.
2. Forgetting the overnight requirement
Distance alone does not qualify a trip. The travel must involve being away from home overnight. Long same-day round trips do not qualify under this provision no matter how far you drove.
3. Deducting the full meal per diem
Meals are capped at the federal M&IE rate and then reduced by the 50 percent limit. Claiming the full per diem roughly doubles the meal portion of your deduction — a clean, easily identified overstatement.
4. Deducting fuel on top of mileage
The standard mileage rate already includes fuel, maintenance, insurance, and depreciation. Adding fuel receipts on top is double-dipping. Only parking, tolls, and ferry fees are deductible separately.
5. Claiming reimbursed expenses
Only unreimbursed costs count. If your unit paid for lodging or issued a travel allowance, subtract it. Reimbursement records exist independently of your return, which makes this an easy discrepancy to spot.
6. Using one mileage rate for all of 2026
2026 is a split year. Trips before July 1, 2026 use 72.5 cents per mile; trips from July 1 onward use 76 cents. Applying a single rate across the whole year produces a wrong number in one direction or the other.
7. Having no contemporaneous records
A deduction you cannot substantiate is a deduction you may lose. Keep a mileage log with dates, destinations, purpose, and miles; keep your orders; keep lodging receipts. Records created near the time of travel are far more persuasive than a reconstruction from memory.
One more worth mentioning
Measuring the 100 miles as a straight line rather than a driving route. Use a normal, defensible driving route — and if your duty location sits near the threshold, save a screenshot of it with your records.