How much does it cost to issue CFDI electronic invoices from your own system in Mexico?

What your system needs to issue an invoice

An electronic invoice, or CFDI, is put together by your system, sealed with your certificate and stamped by a provider authorized by SAT, Mexico's tax authority. For that to happen on its own, your system needs six things:

1. Your digital seal certificate (certificado de sello digital, CSD). It is not the same as the e.firma, SAT's electronic signature. Requesting it from SAT is free, and individuals and companies that will issue invoices can apply.
2. A PAC. This is the certification provider authorized by SAT (proveedor autorizado de certificación) that validates and stamps each invoice. SAT does not charge for its seal. What you pay for is the PAC's service.
3. Each customer's tax data, as it appears on their tax status certificate (constancia de situación fiscal): RFC (the tax ID), name in capital letters, ZIP code of their tax address, tax regime and what they will use the invoice for.
4. Knowing whether you have been paid. If you collect when you invoice, the payment method is PUE (pago en una sola exhibición, a single payment). If you collect later or in parts, it is PPD (pago en parcialidades o diferido).
5. Payment complements. With PPD, for every payment you receive you issue another CFDI with the payment receipt complement (complemento para recepción de pagos), no later than the fifth calendar day of the following month.
6. Cancellation with a reason. SAT asks you to say why you are canceling: errors with a new invoice that replaces it, errors with no related invoice, a transaction that did not happen, or a sale that was already in the global invoice (factura global).

If you take advance payments, SAT has its own procedure for invoicing them, in appendix 6 of its guide to filling out invoices under Annex 20 (Anexo 20). Your system has to follow it or leave that case to your accountant.

The hard part is not stamping. It is having your customers' data entered correctly. An invoice with the wrong tax regime or ZIP code gets canceled and issued again.

SAT's free tool or a PAC with an API

An API is the connection through which one system talks to another. PACs offer one so your system can stamp invoices without anyone typing anything.

Praxium Consultores sums it up this way: SAT's free app is enough for anyone who issues few invoices a month and does not need to integrate their system.

What PACs charge

These are the prices two PACs with an API publish, checked on November 3, 2026. Amounts are in Mexican pesos, and VAT is Mexico's value added tax (IVA).

Illustrative example. Using those published prices, a business that issues 200 invoices a month for a year:

The payment complement is another CFDI, so it gets stamped too. If you collect almost everything after invoicing, plan for twice as many stamps.

The PAC is the smallest part of the cost. What drives the quote is the work of connecting your system: capturing and validating each customer's data, issuing, canceling, emailing the invoice and storing the files. Ask for it as its own line item in the proposal.

What changed in 2026

Invoices must cover real transactions

Since the reform published in the Official Gazette (Diario Oficial de la Federación) on November 7, 2025, the Federal Tax Code (Código Fiscal de la Federación, CFF) requires every CFDI to cover "existing, true transactions or real legal acts" (our translation).

If it does not, the invoice is considered false (article 29 A, section IX). In practice, your system should invoice what actually happened: every invoice tied to an order, a delivery or a payment that can be looked up.

Cancellation has a deadline and often needs acceptance

According to SAT's 2026 cancellation scheme:

• You can cancel no later than the month in which the annual tax return is filed for the year the invoice was issued (article 29 A).
• If acceptance is needed, your customer has three business days to respond. If they do not, the invoice is canceled (rule 2.7.1.34 of the Resolución Miscelánea Fiscal, SAT's annual tax rules).
• Acceptance is not needed, among other cases, for invoices up to $1,000, for payroll, egreso (credit note) and traslado (goods transfer) invoices, or if you cancel within 24 hours of issuing the invoice (rule 2.7.1.35).
• Invoices with a payment complement always need acceptance, whatever the amount.

Your PAC can lose its authorization

In October 2026 it was reported that SAT had revoked several PACs' authorization and had two more in process: five revoked according to El Contribuyente, seven according to IDConline. El Contribuyente estimates that the seven it mentions validated 20.53% of the country's invoicing.

Invoices already issued remain valid, but the customers of a revoked PAC have to switch.

According to IDConline, a revoked PAC can only keep stamping for its current customers for 30 calendar days. That is why switching PACs in your system should mean changing a setting, not rewriting the module.

When integrating invoicing is not worth it

If you invoice little, use SAT's free tool. If you invoice a lot but your sales do not go through a system of your own, an invoicing subscription does the job: Alegra publishes plans from $249 to $699 a month plus VAT, with unlimited invoices.

Integrating it into your system makes sense when every sale, order or payment that already lives there has to come out invoiced without anyone entering it again. If you also take payments online, budget separately for what your payment provider charges.

What to ask whoever builds it

1. That the PAC account and the digital seal certificate are in your name. Without that, the system belongs more to your provider than to you: who owns the source code?
2. That the system stores each customer's tax data and does not let anyone invoice if it is missing.
3. That it issues payment complements when each payment is recorded.
4. That you can cancel from the system, with the right reason.
5. That it keeps the XML of every invoice. The XML is the invoice. The PDF is its printed representation.
6. That switching PACs does not mean reprogramming.

Stamping is also a monthly cost. Add it to the other monthly costs of running your system, which we cover in how much custom software costs in Mexico.