Subtract days from date
Counting backwards works the same way as forwards. Thirty days before 2 March 2026 is 31 January. Subtracting one month instead gives 2 February, because months keep the day number rather than a fixed count.
How to count back from a date
Counting backwards is what deadlines actually require. A filing due on a fixed date with a 21-day notice period needs the date 21 days before, and getting it wrong by a day is the difference between compliant and not. Where the period is defined in working days, use the business-day version. The two diverge quickly, since 21 working days is over four calendar weeks.
Questions
Leave the date as today and set 30 days: the result is shown with its weekday.
No. A month keeps the day number; 30 days is a fixed count and drifts.
28 February, or 29 in a leap year; the day clamps to the shorter month.
No. Use the business day version if the period is in working days.
Yes, and it handles leap years correctly, including 29 February.