Which `UsoCFDI` should I use for a travel reimbursement?

For general reimbursements paid to a supplier, `G03` (General expenses) is the most common code. When using the employee viáticos complement, `CN01` or the current SAT payroll code applies.

Do I need Carta Porte for mileage on sales visits?

No. Carta Porte applies to moving goods on federal roads. Sales visits without merchandise are documented only with the reimbursement CFDI or the viáticos complement.

What happens if the receiver's RFC is wrong?

The PAC rejects the stamp automatically because SAT validates the RFC against its registry in real time. The CFDI isn't stamped and the expense isn't deductible until it is corrected and reissued.

CFDI 4.0 for travel and mileage reimbursement: required fields step by step

Rodrigo Vázquez — Mexican Tax Specialist (SAT, CFDI)

Published: 4/28/2026 • Last reviewed: 4/28/2026 • 8 min read

Practical guide to CFDI 4.0 fields, Nómina and Viáticos complements, Carta Porte, and RFC validations for Mexican reimbursements.

Why CFDI 4.0 rewrote the rules

Since CFDI 4.0 became mandatory, any travel or mileage reimbursement that aims to be income-tax deductible in Mexico must be backed by invoices that meet the new SAT requirements. Version 4.0 introduced tighter validations: exact recipient name and ZIP, tax regime, a CFDI use aligned with the operation, and new `ObjetoImp` and `Exportacion` fields on every line item.[^sat-cfdi40]

Recipient data with zero margin for error

The receiver must be registered exactly as it appears on its Constancia de Situación Fiscal: corporate name in uppercase, active RFC, fiscal-domicile ZIP code, and current tax regime. SAT validates these fields against its taxpayer registry in real time; any mismatch causes the PAC to reject the stamp.

ClaveProdServ 84111506 for travel

For travel expense reimbursements, the recommended product/service key is `84111506` (Employee expense reimbursement services) from SAT's c_ClaveProdServ catalog.[^sat-catalogos] Paired with the right `ClaveUnidad` (`E48` for service unit, or `KMT` when billing by kilometers), it accurately describes the expense and helps reconcile against the accounting entry.

ObjetoImp: the field many people forget

Every CFDI 4.0 line item must declare `ObjetoImp`. For pure reimbursements without VAT, the typical value is `01` (Not subject to tax). If the reimbursement carries a taxable margin, use `02` and itemize the VAT. Getting this wrong causes immediate PAC rejection or, worse, a stamped CFDI that SAT will challenge during an electronic review.[^sat-cfdi40]

Nómina complement when reimbursement runs through payroll

If mileage is paid through the employee's paycheck, the Nómina 1.2 complement must be used with the correct concept in `OtrosPagos` or `Percepciones`. The portion that exceeds tax-exempt thresholds becomes taxable income and generates withheld ISR.

Viáticos complement: the right path

The safest route is to have the employee provide CFDIs for fuel, tolls, and lodging issued in the company's name, and have the company record the reimbursement to the employee as an internal accounting entry reconciled against those invoices.

Carta Porte: when it applies

Carta Porte 3.0 is mandatory only when goods or merchandise move on federal roads.[^sat-cartaporte] Pure mileage reimbursement for sales visits does not require it, but it does apply if the company ships its own product in the employee's vehicle. Mixing up the two scenarios triggers fines starting at 17,000 pesos.

Final pre-stamp checklist

Before sending to the PAC, confirm: recipient RFC and ZIP match the Constancia, correct tax regime, appropriate `UsoCFDI` (`G03` is common for general expenses), consistent `ClaveProdServ` and `ClaveUnidad`, `ObjetoImp` declared on every line, the right complement attached, and a payment method that matches reality. With that discipline, reimbursement turns from a tax risk into a predictable, auditable process.