Excel WORKDAY Formula

Quick answer

The Excel WORKDAY function adds a specified number of working days to a start date, automatically skipping weekends (Saturday and Sunday). The companion function NETWORKDAYS counts the number of working days between two dates. Both support an optional holiday range to exclude UK bank holidays. For the most accurate UK deadline calculations, always include a bank holiday list as the third argument.

Core formulas at a glance

Worked example: FOI deadline in Excel

An FOI request is received on Monday 5 May 2025. Under the FOI Act 2000, the 20 working day clock starts the day after receipt, so day one is Tuesday 6 May. However, 5 May is the Early May bank holiday, so it was already a non-working day. The 20th working day, excluding weekends and the Spring bank holiday (26 May), is Tuesday 3 June 2025.

Step-by-step: setting up a UK deadline spreadsheet

1. Enter your start date in cell A1 (e.g. the date you received the request).
2. Create a holiday list in a separate column (e.g. E2:E10). Include all England and Wales bank holidays for the relevant year. You can copy these from the 2026 bank holiday list or GOV.UK.
3. Choose the right function: Use WORKDAY if you need a future date (FOI deadline, notice period end). Use NETWORKDAYS if you need to count how many working days have elapsed.
4. Decide whether day one is the start date itself or the next working day. For FOI and SAR, the clock usually starts the day after receipt — use =WORKDAY(A1, 1) to find day one, then add the remaining days from there.
5. Test with known dates to verify your formula is correct before relying on it.

Common mistakes to avoid

• Forgetting the holiday range. =WORKDAY(A1, 20) only skips weekends. Without a holiday list, bank holidays are counted as working days, which can push your deadline 1–3 days early.
• Counting from the wrong start date. If the clock starts the day after receipt, do not use the receipt date as day one. Use WORKDAY to find day one first.
• Using calendar days instead of working days. The FOI Act and many complaint procedures specify working days, not calendar days. =A1+20 gives the wrong answer.
• Mixing up WORKDAY and NETWORKDAYS. WORKDAY returns a date; NETWORKDAYS returns a number. Using the wrong one can give misleading results.
• Not updating the holiday list each year. Bank holidays change. Refresh your list annually.

WORKDAY.INTL for non-standard working weeks

If your organisation operates a non-standard working week (e.g. Sunday to Thursday, or a four-day week), use WORKDAY.INTL instead of WORKDAY. The third argument defines which days are weekends using a weekend code:

Example: a team working Sunday to Thursday would use =WORKDAY.INTL(A1, 20, 7, E2:E20) where 7 = Friday/Saturday weekend.

NETWORKDAYS for calculating elapsed working days

If you need to know how many working days have passed — for example, to check whether a complaint response is overdue — use NETWORKDAYS:

• =NETWORKDAYS(A1, TODAY(), E2:E20) counts working days from the start date to today, excluding holidays.
• =NETWORKDAYS.INTL(A1, B1, 1, E2:E20) does the same but lets you customise the weekend definition.

For complaint and FOI monitoring, you can compare the result against the required number of working days (e.g. 8 weeks for FCA complaints, 20 working days for FOI) to see if you are within the deadline.

Key takeaways

• Use =WORKDAY(start_date, days, holiday_range) to find a date N working days from a start point.
• Use =NETWORKDAYS(start_date, end_date, holiday_range) to count working days between two dates.
• Always include a UK bank holiday list as the third argument for accurate results.
• For FOI and SAR deadlines, the clock usually starts the day after receipt — use WORKDAY to find day one separately.
• Verify your formula against a dedicated deadline calculator before relying on it for legal or regulatory purposes.

References

• Microsoft — WORKDAY function reference
• Microsoft — NETWORKDAYS function reference
• GOV.UK — UK bank holidays
• ICO — FOI time for compliance