Excel Add Business Days

There are two ways to “excel add business days”: the quick way you copy and the durable way you understand. This page gives you both. The exact Excel answer is above with a tool to test it; below, we build the small mental model that makes the fix stick, so the next variation of the same problem solves itself.

Exact answer

In Excel: use =NETWORKDAYS(start_date, end_date, [holidays]) — it counts the whole working days (Monday to Friday) between two dates, excluding weekends and any holidays you list.

Syntax

=NETWORKDAYS(start_date, end_date, [holidays])

Arguments

ArgumentDescription
start_daterequiredThe first date of the period, counted as day one.
end_daterequiredThe last date of the period; it is included in the count.
holidaysoptionalA range of dates to exclude as well, such as public holidays.

Related functions

DATEDIFWEEKDAY
ƒxWorkday CalculatorLive
Workdays
62

86 calendar days

=NETWORKDAYS(A2,B2)
Saturdays and Sundays are skipped; public holidays are not.
Ctrl+CthenCtrl+Shift+V+Cthen+Ctrl+VPaste values · WindowsMac

What this does

NETWORKDAYS counts whole working days between two dates. It includes both the start and end date, automatically skips every Saturday and Sunday, and skips any dates you pass in the optional holidays range as well. It is the standard way to work out delivery times, project durations or how many billable days fall in a period. If your week does not run Monday to Friday — say a Sunday-to-Thursday week — use NETWORKDAYS.INTL, which adds a weekend-pattern argument so you can define which days count as the weekend. Most people learn this as a sequence of clicks and forget it by next week; learning it as a pattern instead is what lets you apply it to the next, slightly different version of the problem without starting from scratch. That is the difference this page is trying to make. The difference between a quick fix and a sheet you can trust is the extra minute you spend validating “excel add business days”. Start on a copy or a tiny sample, keep the affected cells visible, and compare the result with the tool above before you touch the real workbook. When a formula is involved, keep the inputs labelled beside it, reference cells instead of typing values, and apply number formatting only after the result checks out. The point is a layout choice that keeps the sheet readable and sortable, but the practical win is that someone else can open the file and understand what happened without asking you.

A worked example

A task starts on 01/06/2026 (a Monday) in A2 and is due 12/06/2026 (a Friday) in B2. =NETWORKDAYS(A2, B2) returns 10 — the two full weeks of weekdays, with the weekend of the 6th and 7th excluded. If 05/06/2026 is a public holiday listed in D2, then =NETWORKDAYS(A2, B2, D2) returns 9, dropping that one day too. NETWORKDAYS is the right tool for SLAs, project timelines and billing, where only Monday-to-Friday working days count and weekends and holidays must drop out automatically. If there is any chance you will reuse this, drop it into a small template tab right now: a labelled input area on the left and the formula beside it, checked once against the tool above. Next time the same question comes up, the answer is a single paste away instead of a rebuild from memory.

In Google Sheets

If you are in Google Sheets rather than Excel, the good news is that the formula shown here is identical and the workflow barely changes — menus sit across the top instead of in a ribbon, and a few function names differ slightly, but anything you build here moves across with little or no rework. Keep this page bookmarked for the next time the same question comes up. Better still, rebuild the example once in your own sheet — doing it yourself, with the tool above to check against, is what turns a copied formula into a technique you own. Here is the takeaway for “excel add business days”: copy the answer if you are busy, but if you have a spare few minutes, rebuild the example in Excel yourself with the tool above open beside it. That single pass — type it, run it, watch the result move when you change an input — is what turns a formula you found into a technique you trust. Keep your inputs labelled and referenced, never hard-coded, and the same sheet stays correct and auditable as it grows. Done that way, you will not need to look this up again, and you will be the person others ask.

Common mistakes

  • Expecting the result to exclude the start date — NETWORKDAYS counts both endpoints, so a Monday-to-Friday span is 5, not 4.
  • Leaving holidays out and over-counting across public holidays; pass a holiday range as the third argument to drop them.
  • Using NETWORKDAYS for a non-Monday-to-Friday week — it always treats Saturday and Sunday as the weekend, so use NETWORKDAYS.INTL for other patterns.

Frequently asked questions

Does NETWORKDAYS include the start and end dates?

Yes, both are counted if they fall on a weekday. A period from Monday to Friday returns 5 because every day in the inclusive range is a working day.

How do I exclude public holidays?

List the holiday dates in a column and pass that range as the third argument: =NETWORKDAYS(A2, B2, D2:D10). Any of those dates that fall on a weekday are removed from the count.

How do I count working days with a different weekend?

Use NETWORKDAYS.INTL, which takes a weekend argument — a code or a 7-character pattern — so you can define, for example, a Friday/Saturday weekend instead of Saturday/Sunday.