FIFO (first in, first out) ships whatever arrived at the warehouse first. FEFO (first expired, first out) ships whatever expires soonest, regardless of when it arrived. They are two different rotation rules, and confusing them is the most common reason a brand ends up discarding product that was still valid on paper.
The difference in one example
You have two lots of the same product in the warehouse:
| Lot | Arrived | Expires |
|---|---|---|
| A | March 10 | September 30 |
| B | May 5 | August 15 |
Under FIFO, the next order ships from lot A, because it arrived first. Lot B stays on the rack and expires in August.
Under FEFO, the next order ships from lot B, because it expires first. Lot A has until September to move.
Lot B arrived later but expires earlier. This happens constantly: different suppliers, different production runs, or goods held up in customs. If your warehouse runs FIFO by default and your product carries a date, you are scheduling waste.
When FIFO is enough
FIFO is sufficient when your product does not expire, or when its shelf life is so long that the date is never the limiting factor: tools, accessories, apparel, home goods, electronics.
Even without expiration, FIFO remains good practice for two reasons: it keeps units from aging at the back of the rack (packaging that fades, boxes that deform) and it keeps inventory costing orderly.
When FEFO is mandatory
FEFO stops being an improvement and becomes a requirement when you sell:
- Food and beverages — including online groceries, a category that grew sharply in Mexico during 2026, as we covered in the Mercado Libre Súper case.
- Supplements and nutrition — covered in supplements fulfillment.
- Cosmetics and personal care with PAO (period after opening) or an expiration date.
- Regulated pharmaceutical and hygiene products.
- Any product with a traceable lot required by the marketplace or the end customer.
In these categories, a marketplace can reject your inventory if remaining shelf life at the time of sale falls below a threshold. It is not enough for the product to be valid: it has to reach the customer with margin to spare.
What it takes to actually run FEFO
This is where many operations stop halfway. FEFO is not a policy you announce, it is a capability you build:
- Capture the expiration date at receiving. If the data does not enter the system when goods arrive, it does not exist. This is failure number one.
- Identify the lot at unit or pallet level, not at SKU level. Two pallets of the same SKU are two different inventories if their dates differ.
- A system that sequences picking by date, not by location. If the system tells the picker "go to aisle 4" without filtering by lot, the rule is not enforced no matter what the manual says. We explain it in what is a WMS.
- Alerts based on remaining shelf life, not on the expiration date itself. Finding out the day it expires helps nobody; finding out 90 days ahead gives you time to liquidate.
- Separate locations by lot when volume justifies it, so the picker does not have to decide.
Without all five, you have FEFO in the contract and FIFO on the floor.
The three costliest mistakes
Trusting that the picker "will grab the front one." Without system control, rotation depends on which pallet is most accessible. That is not a rule, it is chance.
Receiving without recording dates "because it slows us down." You save two minutes at receiving and lose entire cases six months later.
Having no minimum shelf life policy at dispatch. If you ship a product with fifteen days of life left, you technically complied. The customer who receives it will not see it that way, and on a marketplace that is a return with a review attached.
Frequently asked questions
Can I use FIFO and FEFO at the same time? Yes, and that is normal in a warehouse with a mixed catalog: FEFO for dated SKUs, FIFO for the rest. What does not work is applying a single rule to all inventory.
Is FEFO useful if my product expires in two years? Just as useful. A long shelf life only means the mistake takes longer to surface — and when it does, it lands on a bigger inventory.
What about product that is already close to expiring? It gets physically separated and a decision gets made: promotion, alternate channel, or write-off. What should not happen is that it stays mixed into available inventory.
Correct rotation goes unnoticed when it works; it shows up when it is missing, in the form of product written off three months after it was still good. If you want to review how your inventory is rotating today, tell us about your warehousing and we will look at it with your actual lots.