Updated October 2026
FIFO ships stock in the order it arrived. FEFO ships it in order of its use-by date. With formula and baby food, the two give different answers when a newer lot carries an earlier date.
FEFO (first-expired, first-out) ships the lot with the nearest use-by date first. FIFO (first-in, first-out) ships the lot that arrived first. Formula and baby food carry use-by dates, and lots don't always reach the warehouse in date order. When they don't, picking by arrival can leave a shorter-dated lot waiting behind a longer-dated one. Either method can be the right one, depending on the product. On shelf-stable formula and baby food, we record the date at receiving and run FEFO, and near-expiry stock is flagged before it's picked.
By The Fulfillment.com team
Both are rules for deciding which unit leaves the shelf next. FIFO goes by the receiving date, so the unit that came in earliest ships first. FEFO goes by the use-by date, so the unit that expires soonest ships first. For goods with no shelf life, or dated goods whose lots arrive in date order, both rules pick the same units, and a FIFO warehouse still checks the date on the pick. Formula and baby food are different. A can of formula or a pouch of baby food is fed to an infant, and the day a lot arrived and the day it expires don't always line up.
Here is how they come apart. A lot that arrives this week can carry an earlier use-by date than one that has sat on the rack for months. That happens when an inbound lot had already used up part of its shelf life before it reached the warehouse, or when a supplier shipped from older stock. Pick by arrival and the longer-dated lot goes out while the short-coded one creeps toward its date. Eventually a parent opens a tin or jar with only weeks left on it. The unit comes back or draws a chargeback, and the brand loses a customer who is slow to trust again. FEFO prevents that by offering the nearest use-by stock first. It is part of the everyday work of baby products fulfillment.