28 USC 1821: Witness Fees, Per Diem, and Mileage

If you’ve been called as a witness in a federal case, federal witness fees under 28 U.S.C. § 1821 entitle you to a $40 attendance fee for each day you’re required to appear, mileage or actual transportation costs to get there, and a subsistence allowance for lodging and meals if you can’t reasonably return home each night. The same rates apply whether you’re testifying at trial, before a U.S. magistrate judge, or at a deposition ordered by a federal court.¹

Who Can Collect and Who Can’t

Fact witnesses in civil and criminal federal cases qualify, and so do witnesses appearing at court-ordered depositions.¹ A few categories are shut out:

Federal employees testifying in their official capacity don’t receive the attendance fee, because their salary already covers the time. A federal employee who testifies for a private party using annual leave or leave without pay may keep the fee.²
Incarcerated witnesses cannot receive any fees or allowances under the statute. The exception is a material witness detained under 18 U.S.C. § 3144 because they could not post security, who still qualifies.¹
Anyone paroled into the United States for prosecution, or determined to be deportable under the Immigration and Nationality Act, is ineligible.¹

The $40 Daily Attendance Fee

Every eligible witness receives a flat $40 for each day of attendance, whether or not you actually take the stand.¹ If the court requires your presence, you’re paid for the day. The fee also covers each day you spend traveling to and from the place of attendance, and any additional travel days if your appearance is interrupted and resumes later.

The same $40 rate applies to depositions taken under a federal court order. It applies to the deposition day itself and to any necessary travel days that go with it.

Material witnesses detained because they could not post security receive the $40 daily fee for each day of detention on which they are not in court, in addition to their subsistence allowance.¹

Mileage and Transportation Reimbursement

Drive your own vehicle and you’re reimbursed at the same mileage rate the General Services Administration sets for federal employee travel. For 2026 that rate is 72.5 cents per mile.³ Mileage is measured along the shortest practical route between your home and the place of attendance.¹

If you fly, take a train, or use another common carrier, you’re reimbursed for actual costs, but you’re required to use the most economical rate reasonably available. Keep receipts. There is no dollar threshold that waives the receipt requirement.¹ Tolls for roads, bridges, tunnels, and ferries, taxi fares between your lodging and transportation terminals, and parking fees with a valid receipt are all reimbursed on top of the base transportation cost.

Subsistence Allowance for Overnight Stays

When the place of attendance is far enough from home that you can’t reasonably travel back and forth each day, you qualify for a subsistence allowance covering lodging and meals. The amount cannot exceed the GSA’s maximum per diem rate for federal employee travel in that location.¹ For designated high-cost areas, the ceiling is the higher “actual subsistence” rate available to federal employees in those locations.

Per diem rates vary widely by city and season, so what you’ll receive depends on where the court sits. The allowance is a cap on reimbursement, not a flat bonus paid on top of your actual expenses. You can look up the current rate for any location on the GSA’s per diem lookup tool.

What Must Be Tendered With a Subpoena

If you’re the one issuing a subpoena to a private witness, Federal Rule of Civil Procedure 45(b)(1) requires you to tender one day’s attendance fee ($40) plus the mileage allowed by law at the time you serve the subpoena.⁴ Serving without tendering fees can make the subpoena unenforceable.

Subpoenas issued on behalf of the United States or its officers and agencies are exempt from the tender requirement.⁴ Government witnesses get paid after they appear, through the voucher process.

Expert Witnesses Are Paid Differently

An expert witness is technically entitled to the same § 1821 fees, but the real compensation comes from a separate arrangement. The party retaining the expert negotiates a rate, and under Federal Rule of Civil Procedure 26(b)(4)(E) the opposing side seeking discovery from that expert must pay a “reasonable fee” for the expert’s time responding.⁵ If you’re serving as an expert, don’t expect the $40 rate to describe what you’ll actually be paid.

How to Actually Get Paid

Where you send the claim depends on who called you.

If the federal government subpoenaed you, file through the U.S. Marshals Service using a Fact Witness Voucher (Form DOJ-3).⁶ The voucher is usually provided once your attendance is no longer required. Attach receipts for every claimed expense before you submit it.⁷ After processing, a check goes to the address on the voucher.

If a private party subpoenaed you, that party is responsible for your fees and costs. The attendance fee and mileage should already have been tendered when you were served. For anything beyond the first day, including additional attendance, transportation, and subsistence, you’ll need to seek payment directly from the party who called you. If they refuse, you can ask the court to enforce compliance.

Whoever pays you, keep every receipt and log your attendance dates. Vouchers returned for missing documentation are the most common reason payment is delayed.

Taxes on What You Receive

The $40 daily attendance fee is taxable income. The IRS treats witness fees like other miscellaneous income, and if payments to you meet the applicable annual threshold, the paying agency issues a Form 1099.⁸ For 2026, the general reporting threshold for amounts reported in Box 3 of Form 1099-MISC is $2,000, adjusted for inflation.⁹ Even without a 1099, the income is still reportable.

Travel reimbursements that offset actual costs you incurred, such as mileage, lodging, and transportation, are generally not taxable. The attendance fee is income regardless.

1
Office of the Law Revision Counsel. 28 USC 1821 – Per Diem and Mileage Generally; Subsistence
2
eCFR. 28 CFR Part 21 – Witness Fees
3
U.S. General Services Administration. Privately Owned Vehicle (POV) Mileage Reimbursement Rates
4
Legal Information Institute. Federal Rules of Civil Procedure Rule 45 – Subpoena
5
Legal Information Institute. Federal Rules of Civil Procedure Rule 26 – Duty to Disclose; General Provisions Governing Discovery
6
U.S. Marshals Service. DOJ-3 Fact Witness Voucher
7
U.S. Marshals Service. Fact Witness Voucher
8
Internal Revenue Service. 25.5.9 Fees and Costs for Summoned Witnesses
9
IRS. Publication 1099 General Instructions for Certain Information Returns