Written for Mexico. This analysis applies to Mexican federal tax law — ISR (income tax), IVA (VAT) and SAT rules — and cites Mexican statutes. Amounts are in Mexican pesos (MXN).
For the SAT, your payroll is the most transparent process in your company: every peso you pay is stamped in real time and cross-checked against what you report. That's why the employer viewer is, for any company with workers, the first review before the annual return — and the cheapest to run. It shows you the same thing the authority sees, with time to correct.
What the employer viewer shows you
As an employer you're required to issue the payroll CFDI, withhold the ISR and remit it (art. 99 LISR), and that payroll is deductible only if you meet those requirements (art. 27, section V LISR). The employer payroll-receipt viewer concentrates all of that: you log in with e.firma or Contraseña and see, cumulatively and per worker, the payroll CFDI you stamped since 2018 — earnings, deductions, ISR withheld and the employment subsidy. It's not your payroll system or your accounting: it's the official reflection of what ended up stamped with the SAT, which is exactly what the authority uses to cross-check. Access is in our resource center.
How to reconcile: stamped vs. remitted vs. deducted
The reconciliation that matters crosses three sources that should produce the same number. One, what was stamped: the total payroll CFDI for the year according to the viewer. Two, what was remitted: the ISR withheld on the wages you paid, in your monthly returns (the withholding form). Three, what was deducted: the payroll expense you booked into your accounting and your annual return. All three have to tie out. If you stamped $10 but remitted withholdings of $8, you have a remittance shortfall. If you deducted a payroll you didn't fully stamp, that portion isn't deductible. The viewer gives you the first of the three figures, clean and official; you supply the other two.
The three differences the viewer exposes
You stamped and didn't remit. The most serious one: you withheld ISR from your workers and didn't pay it to the SAT. It stops being an oversight — it's one of the sins that escalate to a crime (arts. 99 LISR and 108-109 CFF). You remitted differently from what you stamped. Differences between the ISR on the receipts and the ISR in your returns: almost always data-entry errors or subsidy-calculation errors, correctable with amended returns. You deducted more than you stamped. If your accounting carries payroll expense with no CFDI backing it, that deduction falls apart in a review. The viewer corrects none of them — it shows you where they are so you can close them yourself, with an amended return and with time.
The right order before the annual return
The sequence that avoids surprises: first, download the year's cumulative record from the viewer; second, cross it against your remitted withholdings month by month; third, against the payroll expense in your accounting; fourth, correct whatever doesn't match with amended returns before filing the annual return, while the correction is still voluntary (art. 73 CFF) and costs no penalty. This routine is the operational version of what we explain in payroll and its four authorities: a well-reconciled payroll is the company's most defensible process; an unreconciled payroll is the easiest to audit.
Frequently asked questions
Do I log in to the employer viewer with the Contraseña (password) or e.firma?
You can log in with either e.firma or the SAT Contraseña (password). Since this is company-level information about every worker, many prefer e.firma for access control. It's a read-only consultation: you file nothing, you just review and download the cumulative record to reconcile against your returns and your accounting.
How far back does the employer viewer have data?
It concentrates payroll receipts stamped since 2018, cumulative by fiscal year and with detail per worker. That lets you review not only the current year but prior years still open to SAT review — useful if you suspect a difference carried over from years back.
What do I do if the viewer shows differences?
That depends on which one. If you withheld and didn't remit, remit the shortfall with inflation adjustment and surcharges as soon as possible, ideally before any demand from the authority. If there are data-entry differences between what was stamped and what was reported, correct with amended returns. If you deducted payroll without stamping it, adjust the deduction. Doing it voluntarily, before the SAT notices, avoids substantive penalties.
Does this replace my accounting or my payroll system?
No. The viewer is the official source of what was stamped, not your accounting. It's for reconciling: you cross what the SAT already has against what you recorded and remitted. Reconciliation is precisely finding the differences between the two worlds before the authority finds them in an automatic cross-check.
Do your stamped, remitted and deducted payroll figures match?
Payroll reconciliation is simple to state and easy to postpone — until the SAT cross-check arrives. We run your reconciliation across the three fronts (stamped, remitted, deducted), identify the differences and close them with amended returns before the annual return, while the correction is still voluntary and costs no penalty.