Business days / boundary guide

Check business-day start, end, and holiday rules

Keep the rule beside the number: whether the start or end date is included, and which listed holiday is excluded.

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Five boundary cases

A PASS here means the synthetic fixture agrees with the stated rule and expected value.

Case	Rule	Expected
Start included	Count the start date when it is a business day	1 business day
Start excluded	Begin on the next business day	1 business day
End included	Include the end date when it is a business day	1 business day
End excluded	Stop before the end date	1 business day
Holiday crossing	Exclude the listed holiday separately from weekends	2 business days

Write the rule before the number

The same dates can produce different answers when start or end inclusion changes. For a holiday crossing, record the holiday date and its source separately.

Apr 1 → Apr 1
start: included
answer: 1 business day

Boundary included.

Apr 28 → May 1
Apr 29: holiday
answer: 2 business days

Listed holiday excluded.

Handoff fields

Keep the date range, start/end rules, weekends, holiday date and source, and expected count on the same row. Do not transfer only the final number.

case: holiday-crossing
rule: listed holiday excluded
holiday: 2026-04-29
expected: 2 business days

The fixtures are static. They do not fetch calendars, URLs, or user input.

What this guide does not guarantee

It does not guarantee a company calendar, statutory holiday, timezone, policy deadline, or the settings of the existing calculator. Do not replace a live deadline decision with a synthetic fixture.