On September 8, together with the 2027 Economic Package, Mexico’s Executive sent Congress an initiative to reform the Customs Law. It’s short — it touches only a handful of articles — and it targets one subject: undervaluation.
First, the important part: this is an initiative, not a law. Until Congress approves it and it’s published in the DOF, today’s rules still apply. But it’s worth reading now, for two reasons. First, the proposal says it would take effect the day after publication, with no transition period. Second, what it takes to defend yourself — a solid customs value file — isn’t built in a day.
What the law says today
Today, the authority can precautionarily seize your goods for undervaluation when the value you declared is 50% or more below the transaction value of identical or similar goods.
Put differently: there’s a wide margin. A price 30% or 40% below the authority’s reference can lead to a review, but it doesn’t by itself trigger a seizure at customs.
That’s the framework we described in undervaluation and SAT enforcement. The initiative would change it almost entirely.
What would change
| Topic | Today | Under the initiative |
|---|---|---|
| Precautionary seizure | Gap of 50% or more against identical or similar goods | Any downward gap against identical or similar goods |
| What gets seized | The goods | The proposed wording reaches the goods and the means of transport |
| Guarantee for estimated prices | Can avoid seizure | That exception is removed |
| Infraction presumption | From a 50% gap | From 20% |
| Replacing the seizure | With a guarantee | Depends on the gap: below 20%, a deposit or customs guarantee account; from 20%, cash deposit only. Proposed term: ten business days |
| Verification powers | At the authority’s discretion | Mandatory when value gaps are detected |
The articles involved are few — 151, 153, 154, 177 and an addition to 144 — but they reinforce each other: the authority would gain at once a more sensitive trigger (any gap), a heavier consequence (seizure with fewer ways out) and the obligation to review when it detects one.
The text may change in the legislative debate. Check the approved version before adjusting processes; this is what the initiative says, not what the law will say.
Why the threshold change is the one that matters
Going from 50% to “any gap” isn’t a change of degree. It changes the nature of the question.
Today the question is is my price outrageously low? Under the initiative it would be can I explain why my price is below what the authority has recorded for identical or similar goods?
And there are plenty of legitimate reasons for a lower price:
- Volume: large purchases with a negotiated discount.
- Clearance of stock or end of model.
- Different quality or specification from the goods you’re being compared with.
- A long commercial relationship with its own terms.
- Market timing: a raw material that dropped.
All valid. None of them count if they aren’t documented. That’s the real difference the initiative introduces: the 50% margin worked, in practice, as a cushion for weak files. Without it, the cushion is the file.
The cash-flow side
Even if your value is correct and you end up proving it, the seizure costs money while it resolves.
If the gap reaches 20% or more, the initiative would only accept a cash deposit to replace the seizure. That’s tied-up liquidity. Meanwhile, the container’s storage and demurrage keep running.
So preparation isn’t only legal — it’s financial. It’s worth knowing in advance which shipments are exposed and how much would have to be deposited if one of them stops.
What you can do now, before approval
None of this requires waiting for the DOF:
- Identify your low prices. Cross your main tariff lines and suppliers against market references. The ones that fall below are your exposure.
- Build the value file for those shipments first. Contract, purchase order, proof of payment, credit notes and, above all, the support for why the price is what it is: the volume agreement, the clearance sale, the technical sheet showing it isn’t the same goods.
- Check whether your goods are subject to estimated prices. That’s where the initiative removes the guarantee exit.
- Review dutiable additions. Part of “accidental” undervaluation isn’t a low price but freight, insurance or royalties that were never added. It’s the cheapest correction there is.
- Use the MVE. From October 1 the Electronic Value Declaration is mandatory. The value is going to be recorded anyway; make sure it’s recorded right.
If you’ve already found an error in past shipments, the moment to fix it is before the authority asks: a spontaneous correction is treated in a way a formal request isn’t.
How it fits with the rest of the year
This isn’t an isolated change. It’s the fourth piece pointing in the same direction:
- The Customs Law reform that took effect in January.
- The amended Regulations, which expanded the grounds to reject declared value.
- The MVE, mandatory from October.
- And now, this initiative on the seizure threshold.
The pattern is consistent: customs value stopped being a data point on the entry and became a file that gets reviewed, cross-checked and defended. The customs value declaration guide explains how it’s determined; what changes now is the cost of not being able to support it.
If a shipment does get stopped, the map of what to do with goods held at customs and PAMA and precautionary seizure still apply.
We’ll update this article when the initiative is approved, amended or dropped.
At TradeWay
We review value before clearance, not after the request: dutiable additions, price support and a complete file, as part of the same flow as the entry. One point of contact and one invoice for the whole operation. If you want to know which of your shipments would be exposed under a 20% threshold, get in touch.
