How the count works
Counting begins the day after the start date. "Ten business days from Friday" means the tenth working day following that Friday, not the Friday itself plus nine. This is the usual reading of a deadline expressed as "within ten business days", and it is what courts and contracts generally assume.
If your contract counts the start date itself, subtract one from the answer. The difference matters most on short deadlines: "three business days" is a third longer if you count the first day.
A worked example
Ten working days after Friday 18 December 2026 is Tuesday 5 January 2027 — the figures this page loads with. The range contains Christmas Day (Friday 25 December) and New Year's Day (Friday 1 January), plus three weekends.
Ten working days sounds like two weeks. Here it spans eighteen calendar days, because six of them are weekend days and two are holidays. The same ten working days starting on a Friday in March would land fourteen calendar days out — four days sooner. That gap is why deadlines set in December catch people out.
What counts as a business day
Monday to Friday, excluding public holidays. It is not a term with one fixed legal definition, which is why a well-drafted contract says whose holidays apply. Weekends are excluded everywhere. Which holidays count varies by country, by state, and sometimes by industry — banking, courts and shipping all keep different calendars.
This calculator uses the eleven US federal holidays and names every one it skipped, so you can see whether the definition matches the one in your agreement.
The eleven federal holidays
New Year's Day, Martin Luther King Jr. Day, Washington's Birthday, Memorial Day, Juneteenth, Independence Day, Labor Day, Columbus Day, Veterans Day, Thanksgiving and Christmas Day.
Dates are computed rather than listed, including the observance rule: a fixed-date holiday on a Saturday is observed the Friday before, and one on a Sunday the Monday after. Independence Day 2026 falls on a Saturday, so the holiday is Friday 3 July.
What this does not do
- It does not include state, local or company holidays. Federal holidays only. Your organisation almost certainly closes on more days than these.
- It does not know your contract's definition. If your agreement defines business days differently — bank days, court days, days the office is open — use its definition.
- It is not legal advice, and a deadline that matters should be checked against the agreement that created it.
Common questions
Does the start date count?
No. Counting starts the following day, which is the standard reading of "within X business days". If yours counts the start date, subtract one.
Are working days and business days the same?
In ordinary use, yes — Monday to Friday excluding public holidays. Some industries use "working day" to mean a day their own operation is open, which can be a shorter list.
Why does my answer differ from another calculator?
Almost always one of three things: whether the start date is counted, which holidays are included, or whether observed dates are used for holidays falling at a weekend. This tool lists the holidays it skipped so you can find the difference rather than guess at it.
References
- OPM — federal holidays and the in-lieu-of rule.
- Federal Reserve — bank holiday schedule, if your deadline is a banking one.