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Expiry vs Expiration: Same Meaning, Label Rules
Expiry vs expiration: same meaning, different region. See which word US label rules use and the YYYY-MM-DD date format on medical device labels.
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How do Expiration, Expiry compare side by side?
The table below compares Expiration, Expiry across 10 procurement-relevant dimensions, from meaning through source.
Side-by-side comparison
| Dimension | Expiration | Expiry |
|---|---|---|
| Meaning | The coming to an end or termination of something, such as a period, a shelf life or an agreement. | The same: the end or termination. Dictionaries cited by the Canadian Department of Justice add that it is used especially for the end of a time fixed by law, contract or agreement. |
| Is there a difference in substance? | No. It is the ordinary word in American usage. | No. It is the ordinary word in British usage and is common in contracts. |
| Legal English preference (Garner, as cited by Justice Canada) | Preferred in American legal English. | Preferred in British legal English. |
| Wording in US federal label rules | 21 CFR 801.18 (device labels) and 21 CFR 201.17 (drug labels) both say "expiration date". | Not the wording used in those two sections. |
| Use in one government regulations | Appears 450 times in Canadian federal regulations. | Appears 139 times in the same regulations, so both words coexist in one legal system. |
| Date format on a US medical device label | If a device label carries a printed expiration date, date of manufacture or any other date, 21 CFR 801.18 requires four-digit year, two-digit month, two-digit day, separated by hyphens: 2014-01-02. | The rule covers "a printed expiration date, date of manufacture, or any other date", so the format does not depend on which word you write in running text. Combination products bearing an NDC number are exempt. |
| Where a US drug expiration date must appear | When a drug expiration date is required, 21 CFR 201.17 says it appears on the immediate container and on the outer package, unless it is easily legible through the outer package. | Same rule. Single-dose containers packed in individual cartons may carry the date on the carton instead. |
| Best before and use by | Out of scope here: this page covers medical and laboratory labels, not food-date phrases. | Out of scope here, for the same reason. |
| When to pick each | Writing for a US audience, quoting US regulations, or writing about US-labelled medical and lab products. | Writing for a UK or Commonwealth audience, or drafting contract wording. Whichever you pick, use it consistently in a document. |
| Source | 21 CFR 801.18 and 21 CFR 201.17 (eCFR, read 2026-11-01). | Department of Justice Canada, Legistics, "Expiry, Expiration and End" (read 2026-11-01). |
Common questions
Common questions about Expiration vs Expiry
Is expiry the same as expiration?
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Yes in meaning. Both words mean the end or termination of a period. The choice is regional: expiration is preferred in American legal English and expiry in British legal English (Garner, as cited by the Department of Justice Canada). Canadian federal regulations use both, 450 and 139 times respectively.
What is the date format for an expiration date on a medical device label?
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For US medical device labels, 21 CFR 801.18 requires the year in four digits, then the month and day in two digits each, separated by hyphens, for example 2014-01-02 for January 2, 2014. Combination products bearing an NDC number are exempt from that paragraph.
Is best before the same as an expiry date?
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This page covers medical and laboratory product labels. Food-date phrases such as best before are outside it, and it makes no claim about their meaning. On US medical device and drug labels the regulated wording is expiration date.
Is a use by date the same as an expiration date?
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For US drug labels, 21 CFR 201.17 speaks of an expiration date that appears on the immediate container and the outer package. This page does not define use by dates, which belong to other labeling contexts.
Where does the expiration date go on a drug package?
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Under 21 CFR 201.17, on the immediate container and also the outer package, unless it is easily legible through the outer package. Single-dose containers packed in individual cartons may carry it on the carton instead.
