How Long Is 90 Days? Weeks, Months and Business Days
90 days is 12 weeks and 6 days. It is often treated as “three months”, but it usually ends a day or two before the three-month date. It contains 64 or 65 weekdays, and 59 to 64 US working days once holidays are taken out.
Key facts
- 90 days = 12 weeks and 6 days = 2,160 hours.
- 90 days ends up to 2 days before “3 months later”, depending on the start month.
- 90 days contains 59 to 64 US federal working days.
90 days vs 3 months, from the 1st of each month in 2027
| Start | 90 days later | 3 months later | Working days (US) |
|---|---|---|---|
| Jan 1, 2027 | Thu, Apr 1, 2027 | Thu, Apr 1, 2027 | 62 |
| Feb 1, 2027 | Sun, May 2, 2027 | Sat, May 1, 2027 | 63 |
| Mar 1, 2027 | Sun, May 30, 2027 | Tue, Jun 1, 2027 | 64 |
| Apr 1, 2027 | Wed, Jun 30, 2027 | Thu, Jul 1, 2027 | 62 |
| May 1, 2027 | Fri, Jul 30, 2027 | Sun, Aug 1, 2027 | 62 |
| Jun 1, 2027 | Mon, Aug 30, 2027 | Wed, Sep 1, 2027 | 62 |
| Jul 1, 2027 | Wed, Sep 29, 2027 | Fri, Oct 1, 2027 | 62 |
| Aug 1, 2027 | Sat, Oct 30, 2027 | Mon, Nov 1, 2027 | 63 |
| Sep 1, 2027 | Tue, Nov 30, 2027 | Wed, Dec 1, 2027 | 60 |
| Oct 1, 2027 | Thu, Dec 30, 2027 | Sat, Jan 1, 2028 | 60 |
| Nov 1, 2027 | Sun, Jan 30, 2028 | Tue, Feb 1, 2028 | 59 |
| Dec 1, 2027 | Tue, Feb 29, 2028 | Wed, Mar 1, 2028 | 60 |
Only a start of January 1 gives the same answer both ways. Starting February 1, 90 days goes one day past three months because February is short. For most other starts, 90 days ends one or two days early.
Where 90-day periods show up
- Probation periods for new jobs.
- Visa-free stays, such as the 90 days in any 180-day period in the Schengen Area.
- Return and warranty windows.
- Notice periods and payment terms.
Because each of these is written either in days or in months, the exact end date can differ by a couple of days. Use the wording in your document.
Find your exact date
Our 90 days from today page shows the exact date, weekday and business days from today, and 3 months from today shows the month-based answer. For a period starting on another date, the calculator on any of those pages lets you pick a start date.
Sources
- Dates and working day counts: our own calculation.
- U.S. Office of Personnel Management: Federal holidays
