Commercial & Statutory Date Calculator

Add Business Days Calculator

Add or subtract business days from any start date. The calculator automatically skips Saturdays and Sundays and optionally excludes observed US federal holidays for contract notices, ACH banking cutoffs, SLA windows, and settlement timelines.

Counting Basis

Day-0 Rule

Start date excluded; next open day = Day 1

Standard Workweek

Mon – Fri

Skips all Saturdays & Sundays

US Federal Holidays

11 Observed

5 U.S.C. 6103 Fri/Mon shifts

Backward Offsets

Supported

Enter negative days (e.g., -2 ACH)

Configure calculation

Set a start date, choose add or subtract, and pick common business intervals.

Calculation Direction

Start date

Business days (counting forward)

Common Business IntervalsClick to apply

Exclude US federal holidays

Skips standard US federal observed holidays (OPM / Federal Reserve schedule).

Target Date

2026-05-20

Wednesday

Calendar Span

14 days

2.0 wks elapsed

Weekends Skipped

4 days

Sat & Sun skipped

Holidays Skipped

0 holidays

US Federal observed

Day-by-Day Calculation Audit

Chronological verification of business days counted and non-working days skipped.

Step	Date	Day	Classification
Start	2026-05-06	Wednesday	Start date
#1	2026-05-07	Thursday	Business day 1
#2	2026-05-08	Friday	Business day 2
Skip	2026-05-09	Saturday	Weekend (Skipped)
Skip	2026-05-10	Sunday	Weekend (Skipped)
#3	2026-05-11	Monday	Business day 3
#4	2026-05-12	Tuesday	Business day 4
#5	2026-05-13	Wednesday	Business day 5
#6	2026-05-14	Thursday	Business day 6
#7	2026-05-15	Friday	Business day 7
Skip	2026-05-16	Saturday	Weekend (Skipped)
Skip	2026-05-17	Sunday	Weekend (Skipped)
#8	2026-05-18	Monday	Business day 8
#9	2026-05-19	Tuesday	Business day 9
#10	2026-05-20	Wednesday	Target date (Day 10)

1. Day-0 vs. Day-1 Counting Convention & Worked Examples

Across commercial contracts, financial clearinghouses, and statutory notice rules, business day arithmetic follows the Day-0 Exclusion Convention: the date on which an event, order, notice, or trade occurs is treated as Day 0, and Day 1 is the next eligible Monday–Friday working day. If a trigger event happens on a Saturday, Sunday, or observed holiday, Day 0 remains that non-business date and Day 1 begins on the first open business day thereafter.

When federal holiday exclusion is enabled, weekend fixed-date holidays shift to their official weekday observance—Saturday holidays roll back to Friday (for example, July 4, 2026 is observed on Friday, July 3, 2026) and Sunday holidays roll forward to Monday. For a deeper breakdown of contractual cutoffs, read our guide on How Business Days Work in Contracts and ACH Banking .

Scenario	Start Date (Day 0)	Offset	Dates Skipped	Resulting Target Date
Standard SLA Window	Thu, May 7, 2026	+5 Days	1 weekend (May 9–10)	Thu, May 14, 2026 (7 cal. days)
Monday Holiday Crossover	Wed, May 20, 2026	+5 Days	May 23–24 weekend + Mon, May 25 (Memorial Day)	Thu, May 28, 2026 (8 cal. days)
Friday Observed Holiday	Mon, Jun 29, 2026	+10 Days	Fri, Jul 3 (Jul 4 Observed) + 2 weekends (Jul 4–5, Jul 11–12)	Tue, Jul 14, 2026 (15 cal. days)
30-Day Contract Cure Notice	Mon, Nov 2, 2026	+30 Days	6 weekends (12d) + Veterans Day (Nov 11) + Thanksgiving (Nov 26)	Wed, Dec 16, 2026 (44 cal. days)
ACH Payroll Funding Cutoff	Fri, Nov 27, 2026	-2 Days	Thu, Nov 26 (Thanksgiving Federal Reserve closure)	Tue, Nov 24, 2026

2. Real-World Banking, Securities, SLA & Legal Deadline Rules

Not every institution defines a business day identically. Before committing to a wire transfer, securities trade, or court filing, verify which institutional calendar governs your deadline:

SEC T+1 Securities Settlement (17 CFR § 240.15c6-1)

US equities, corporate bonds, ETFs, and municipal securities settle on a T+1 (Trade Date plus 1 business day) cycle. A stock sold on Friday settles on Monday—or Tuesday when Monday is an NYSE/Federal Reserve holiday. Note that bond markets (SIFMA) and stock exchanges occasionally differ on Good Friday (NYSE closed; Federal Reserve open) and Columbus/Veterans Day (NYSE open; banking settlement paused!).

Nacha ACH 1–2 Banking Day Processing

Standard Automated Clearing House (ACH) direct deposits, B2B vendor EFTs, and IRS tax debits settle in 1 to 2 banking business days. Under Nacha Operating Rules, a banking day requires the Federal Reserve FedACH system to be open—excluding weekends and all 11 federal holidays. Submitting a batch after your bank's daily afternoon cutoff (e.g., 5:00 PM EST) pushes Day 0 to the next open banking day. See How Federal Holidays Affect Payroll & Pay Dates .

Commercial SLA Response & Contract Cure Windows

Master Services Agreements (MSAs), software support SLAs, FOIA public-record statutes (typically 5 to 20 business days), and real estate escrow contingencies specify business days so weekend requests do not breach compliance on Monday morning. Always check whether the contract defines business hours Cutoff (e.g., notices sent after 5:00 PM recipient local time are deemed received on the next business day).

Legal Filing Deadlines & FRCP Rule 6(a)

Under Federal Rule of Civil Procedure 6(a), federal court deadlines stated in "days" follow a "days-are-days" calendar count (excluding Day 0, counting intermediate weekends/holidays, and rolling forward only if the final day lands on a weekend, legal holiday, or court-inaccessible day). Conversely, state statutes, Truth in Lending (TILA) 3-day rescission rules, and private agreements specifying "business days" skip intermediate non-working days.

CSV

Complete 2027 week calendar comparing 52-week ISO boundaries against US week numbering.

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Frequently asked questions

Does Day 1 start on the selected date or the next business day?

Standard commercial, banking, and legal counting uses the Day-0 exclusion rule: your selected start or trigger date is Day 0, and Day 1 is the very next eligible weekday (Monday through Friday) that is not an observed holiday. For example, adding 1 business day to a Friday lands on Monday (or Tuesday if Monday is a federal holiday).

How can I subtract business days to find a payroll or filing cutoff?

Enter a negative number of business days (such as -2 or -5) in the calculator. Counting backward skips Saturdays, Sundays, and any enabled observed US federal holidays—ideal for computing 2-day ACH payroll funding deadlines or pre-closing escrow disclosures.

How do weekend federal holidays (such as Saturday, July 4, 2026) affect the calculation?

Under US federal observance rules (5 U.S.C. 6103(b)), when a fixed-date holiday falls on a Saturday, it is observed on the preceding Friday (Friday, July 3, 2026). When it falls on a Sunday, it is observed on the following Monday. Turning on the US federal holiday option automatically skips these observed weekday closures.

What is the difference between a business day and a banking day?

A general corporate business day is any Monday-through-Friday when private offices are open, whereas a banking day requires Federal Reserve payment rails (FedACH and Fedwire) to be open. On holidays like Columbus Day and Veterans Day, many private companies operate normally, but the Federal Reserve is closed—so ACH direct deposits and securities settlements do not clear.

Does Federal Rule of Civil Procedure 6(a) count business days or calendar days?

Since the 2009 amendments to Federal Rule of Civil Procedure 6(a), statutory federal court deadlines expressed in 'days' count every intermediate calendar day (including weekends and holidays), rolling forward only if the final day lands on a Saturday, Sunday, or legal holiday. However, private contracts, state statutes, and agency regulations that explicitly specify 'business days' exclude every intermediate weekend and holiday.