How the expiry date is worked out
The calculator adds the validity period to the issue date. Years and months are counted in calendar months, so a one-year certificate issued on 29 February expires on 28 February the following year. Periods given in days are counted exactly.
Issuers do not all follow the same rule. Some set the expiry to the day before the anniversary, and some to the end of the month. If a date is printed on the document, that date wins. The calculator is for when it isn't, or for planning ahead.
Choosing when to be reminded
The schedule shown, 30, 14, 7 and 1 days before, is the one ExpiryLedger uses by default. Thirty days leaves time for one round of chasing. The later reminders catch whatever the first one did not.
Anything that needs work before it can be renewed needs a longer lead: training hours, a medical, an inspection, a broker who needs updated figures. Use 60 or 90 days for those, because the deadline is really the date the work has to start.
Keeping track of more than one
A calculator answers one date. The difficulty starts at twenty, when certificates are issued at different times and renew on different cycles. The free template holds them in one sheet with the status worked out for you. A tracker goes further and sends the reminders itself.
Common questions
- Is a certificate valid on its expiry date?
- Usually yes: most documents are valid through the date shown unless they say otherwise. Some specify an exact time, so check the wording on anything where a single day matters.
- How long is a certificate of insurance valid?
- A COI reflects the policy it evidences, and most business policies run for twelve months. The certificate's own dates show the policy period, and that is what to track.
- Why does one year from 31 January land on 31 January, but one month lands on 28 February?
- Months are counted in the calendar. When the target month is shorter, the date moves to that month's last day rather than spilling into the next month.
- Is anything I enter stored?
- No. The calculation runs in your browser, and nothing you type is sent anywhere.
Next year, don't work it out by hand
ExpiryLedger remembers every date and emails you — and whoever holds the document — before it matters. Free for 25 items, no card.
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