Add or Subtract Business Days
Find deadlines, notice periods, and project dates. Excludes weekends and optionally US Federal holidays.
Why Time Matters
Why: Contracts, notices, and deadlines often use business days. 30-day notice = 30 weekdays, not 30 calendar days. Tax extensions use business days.
How: Step forward/back one day at a time. Count only MonโFri. Skip US Federal holidays when enabled. OPM observance rules apply.
- โMonโFri only
- โOptional federal holidays
- โAdd or subtract
- โOPM holiday schedule
Add or Subtract Business Days
Find deadlines, notice periods, and project dates. Excludes weekends and US Federal holidays.
๐ Quick Examples โ Click to Load
Start Date
Day Type Breakdown
Calendar vs Business Days
๐ Calculation Breakdown
For educational and informational purposes only. Verify with a qualified professional.
๐ Time Facts
US has 11 federal holidays; SatโFri, SunโMon observance
โ OPM
Typical year has ~252โ260 business days
โ timeanddate.com
2-week notice = 10 business days, not 14 calendar days
โ Labor
๐ Key Takeaways
- โข Business days are Monday through Friday, excluding federal holidays
- โข Tax filing extensions (e.g., Form 4868) typically allow 6 months (~78 business days) from original deadline
- โข A 2-week notice equals 10 business days, not 14 calendar days
- โข Many lease and contract notices require 30โ60 business days advance notice
๐ก Did You Know?
๐ How Business Days Are Calculated
We start from your date and step forward (or backward) one calendar day at a time. Each day that is a weekday (MonโFri) and not a US Federal holiday counts as one business day. Weekends and holidays are skipped.
Federal Holiday Observance
When a holiday falls on Saturday, it is observed the preceding Friday. When it falls on Sunday, it is observed the following Monday. Our calculator uses the official OPM schedule.
The 11 US Federal Holidays (2026)
Our calculator excludes these when "Exclude US Federal Holidays" is enabled:
- New Year's Day (Jan 1)
- Martin Luther King Jr. Day (3rd Monday in January)
- Presidents Day (3rd Monday in February)
- Memorial Day (Last Monday in May)
- Juneteenth (June 19)
- Independence Day (July 4)
- Labor Day (1st Monday in September)
- Columbus Day (2nd Monday in October)
- Veterans Day (November 11)
- Thanksgiving (4th Thursday in November)
- Christmas Day (December 25)
๐ฏ Expert Tips
๐ก Notice Periods
Always confirm whether your contract means calendar days or business days. 30 days notice can be 6+ weeks in business days.
๐ก Tax Deadlines
Form 4868 extends your filing deadline by 6 months. Use 78 business days from April 15 to plan extension deadlines.
๐ก Lease & Contract Notices
Many leases require 30 or 60 days written notice. Use this calculator to find the exact date you must give notice to vacate or renew.
๐ก Banking & ACH
ACH transfers often take 1โ3 business days. Plan around weekends and holidays when expecting deposits or making time-sensitive payments.
โ๏ธ Comparison: Business Days vs Calendar Days
| Scenario | 30 Calendar Days | 30 Business Days |
|---|---|---|
| Typical span | ~4.3 weeks | ~6 weeks |
| Weekends included | Yes | No (excluded) |
| Holidays included | Yes | No (if enabled) |
| Use case | General deadlines | Contracts, notices, banking |
โ Frequently Asked Questions
What counts as a business day?
A business day is typically Monday through Friday, excluding US Federal holidays. Weekends (Saturday and Sunday) are not business days.
Does the calculator exclude federal holidays?
Yes, when you enable "Exclude US Federal Holidays," we skip all 11 federal holidays per year using the official OPM observance rules.
How many business days are in a year?
Typically 252โ260, depending on how weekends and holidays fall. Our calculator handles any date range.
What is a 30-day notice in business days?
30 business days is roughly 6 calendar weeks. Use the calculator to get the exact end date from your start date.
Do banks use business days?
Yes. ACH transfers, check clearing, and many financial transactions use business days. Federal holidays align with bank closures.
Can I subtract business days?
Yes. Choose "Subtract" to go backward from your start date. Useful for "X business days before" deadlines.
What about state holidays?
This calculator uses only US Federal holidays. State and local holidays vary; add buffer if your context requires them.
How accurate is the federal holiday list?
We compute holidays using OPM rules. Dates are accurate for 2020โ2030. For other years, verify against opm.gov.
๐ Business Days by the Numbers
๐ Official Data Sources
๐ Approximate Business Days to Calendar Weeks
As a rule of thumb: 5 business days โ 1 calendar week, 10 business days โ 2 weeks, 20 business days โ 4 weeks, 30 business days โ 6 weeks. With federal holidays, add roughly 1โ2 extra calendar days per month in the span. Use this calculator for exact results.
| Business Days | Approx. Calendar Span |
|---|---|
| 5 | 1 week |
| 10 | 2 weeks |
| 15 | 3 weeks |
| 20 | 4 weeks |
| 30 | 6 weeks |
| 60 | ~3 months |
| 90 | ~4.5 months |
๐ Common Business Day Scenarios
- โข Payroll: Many employers process payroll within 5โ10 business days of month end
- โข Contract termination: 30 or 60 business days notice is common in employment and lease agreements
- โข Tax extensions: Form 4868 gives 6 months from April 15 โ use 78+ business days to plan
- โข Shipping: "Ships in 3โ5 business days" excludes weekends and holidays
- โข Legal deadlines: Court filings and responses often use business days
๐ Business Days vs Calendar Days: When to Use Each
Use business days when the activity only happens on workdays: banking, court filings, government submissions, contract notices, shipping estimates, and payroll. Use calendar dayswhen the timeframe is continuous: medication schedules, rental periods, subscription billing, or any "X days from now" that doesn't specify business days. When in doubt, check your contract or policy โ it will usually say "calendar days" or "business days" explicitly.
Some jurisdictions define "business days" differently. In finance, a business day may exclude market holidays (e.g., Good Friday for stock markets). For legal purposes, "business days" typically means court-open days. Our calculator uses the standard definition: weekdays plus US Federal holidays excluded when the option is enabled.
When subtracting business days, we step backward from the start date. This is useful for "X business days before" deadlines โ e.g., "submit 10 business days before the event" or "cancel 30 business days prior to renewal."
โ ๏ธ Disclaimer: This calculator uses US Federal holidays only. State, local, and international holidays are not included. Verify critical deadlines with your contract, employer, or legal advisor. Not legal or tax advice.
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