Few pieces of food packaging generate as much unnecessary waste as a misunderstood date stamp. Knowing which phrase you're actually looking at changes what it means for whether that food is still good to eat.

The three common phrases

"Best by" or "best if used by" refers to peak quality — flavor and texture may decline after that date, but the food isn't automatically unsafe. "Sell by" is a signal to the retailer for inventory rotation, not a household deadline at all. "Use by" is the closest to an actual safety-relevant date, most often seen on infant formula and some perishables.

There's no single federal standard

In the US, other than infant formula, there's no single federal standard requiring these dates or defining them uniformly, which is why wording varies so much brand to brand. Manufacturers largely set these dates themselves, based on their own quality testing.

Why the inconsistency exists

Because states and localities have historically layered their own additional date-labeling requirements on top of a patchwork federal framework, the same product can be required to carry different phrasing depending on where it's sold, which is part of why a shopper might encounter "sell by," "best by," "use by," and "expires on" all within the same grocery trip, sometimes on very similar products. The USDA and FDA have both pushed in recent years toward encouraging manufacturers to standardize around "best if used by" for quality and "use by" for safety specifically, though adoption across the industry has been gradual rather than universal.

This regulatory patchwork is exactly why comparing a printed date across two different brands of the same food, or the same brand sold in two different states, isn't a reliable way to judge relative freshness — one manufacturer's conservative "best by" estimate can land weeks earlier than another's more optimistic one for what is functionally a very similar product, simply because each company set its own testing standard and its own tolerance for quality decline before printing a date.

Some countries outside the U.S. have moved toward a more standardized two-tier system specifically to reduce this kind of confusion, distinguishing a safety-relevant "use by" from a quality-only "best before" more consistently across all packaged food, not just a handful of exception categories like infant formula. Whether the U.S. eventually converges on a similarly standardized system remains to be seen, but in the meantime, the phrase-by-phrase distinctions above are the most reliable way to interpret what's actually printed on a given package, rather than assuming every date carries the same weight regardless of the specific word next to it.

The exception that is actually about safety

Your senses still matter more than the printed date for most shelf-stable and refrigerated foods: off smell, sliminess, or visible mold are the real safety signals. Infant formula is the clear exception where the "use by" date should be followed strictly.

How to judge specific food categories

Shelf-stable pantry items like canned goods, rice, and pasta are generally safe well past a "best by" date if the packaging is intact, with quality being the only thing that gradually declines. Refrigerated items like deli meat, soft cheese, and ready-to-eat salads deserve more caution and closer attention to sensory cues, since these categories carry a higher baseline risk of bacterial growth even before a printed date is reached. Frozen food is essentially safe indefinitely from a safety standpoint as long as it stays frozen, with a "best by" date on frozen items reflecting quality — texture and flavor — rather than any safety concern at all.

A simple rule of thumb

A can of beans a week past its "best by" date is very likely fine; a "best by" date is a quality estimate, not a safety cutoff, and treating every one as an expiration date is one of the biggest drivers of avoidable household food waste.

The USDA has specifically flagged confusion over date labeling as a meaningful contributor to household food waste in the U.S., since a printed date, however conservatively set by the manufacturer, tends to get treated by shoppers as a hard safety cutoff rather than the quality estimate it usually is. Learning the difference between "best by," "sell by," and "use by" isn't just a label-reading skill — it's one of the more effective, low-effort ways to cut down on food thrown away that was still perfectly fine to eat.

For anyone building a lower-sodium or otherwise carefully managed pantry, that food-waste angle has a practical financial dimension too: no-salt-added canned goods and other specialty lower-sodium products often cost more per unit than their regular counterparts, which makes discarding one prematurely over an overly cautious reading of a "best by" date a genuinely avoidable expense on top of the waste itself, and one more reason it's worth learning to trust your senses over the printed date for most shelf-stable staples.