Calendar Days Against Business Days
A period of five days and a period of five business days can end more than a week apart, and around a holiday the gap is wider still. Systems draw the line by length, by subject, or by nothing consistent at all, so the rule has to be read rather than guessed at.
The rule in short
Some periods run through weekends and holidays and some skip them, and the distinction is usually drawn by the length of the period or stated expressly in the rule. Getting it wrong on a short period is the single most common counting error, because the wrong convention produces a plausible date rather than an obviously absurd one.
The difference between five days and five business days is two days in an ordinary week and more around a holiday. Both conventions are in use, sometimes inside the same instrument, and neither is the obvious default.
What each term means
Calendar days run continuously. Every day counts, including weekends and public holidays, and the period simply runs from the trigger to its end.
Business days skip closures. Weekends and recognized holidays are not counted at all, so the period stretches across the calendar.
Working days may differ again. Some instruments distinguish working days from business days, particularly where a bank or a registry has its own calendar.
The definition is local. Which holidays count depends on the forum, the state and sometimes the office, and a national list is not always the right one.
Clear days exclude both ends. A further convention, used in some systems, excludes the day of the act and the day of the deadline from the count.
Contracts adopt whichever they like. An agreement can define a business day however it pleases, including by reference to a particular market or a particular country.
The convention affects the trigger too. A period that starts on a closure day still starts there; only the ending is adjusted, per weekends, holidays and closures.
Which one applies
The rule says so, or it does not. An unqualified reference to days generally means calendar days in modern procedural codes.
Older rules used a length threshold. Periods below a stated number of days once excluded weekends automatically, and several systems have since removed that.
Amendments changed the position. Where a system moved to counting all periods in calendar days, older commentary and old habits still describe the previous rule.
Agency practice varies. Regulations sometimes specify business days for internal steps and calendar days for external ones, in the same part.
Contracts are the worst offenders. Agreements use business days without defining them, leaving the calendar to be argued about later.
Check the instrument, not the habit. The convention is a property of the rule being applied rather than of the person applying it, and habits travel between forums.
Look for a definition section. Where an instrument defines business day, that definition governs every use of the term inside it and settles the argument.
| Convention | Weekends | Holidays | Typical use |
|---|---|---|---|
| Calendar days | Counted | Counted | Most modern procedural rules |
| Business days | Skipped | Skipped | Short internal steps, contracts |
| Working days | Skipped | Varies | Registries and banking |
| Clear days | Counted | Counted | Both ends excluded |
| Named date | Not applicable | Not applicable | Dates fixed by order |
Where the difference bites
Short response windows. A three or five day period is where the two conventions diverge most sharply in proportional terms.
Periods spanning a holiday weekend. A long weekend can add two or three days to a business-day period and nothing to a calendar one.
Deadlines near the end of a year. Clusters of holidays make the two conventions produce dates a week apart.
Chains of dependent steps. Where one period starts when another ends, an early error compounds through the sequence.
Service adding further days. Added time for posted service interacts with both conventions, per added time for service by mail.
Cross-border matters. Holidays differ by country, so a business-day period involving two jurisdictions needs both calendars.
On any period short enough for the convention to matter, working out both dates takes a minute and settles the question. Using the earlier of the two costs nothing and removes an entire class of error from the calculation.
Holidays, and which ones count
Federal and state lists differ. A day that closes one office leaves another open, and the relevant list is the one for the office where the step is taken.
Local closures are not always holidays. An office closed for weather or maintenance is dealt with under closures rather than the holiday list, per weekends, holidays and closures.
Half days. An office open for part of a day is usually open for the purposes of counting, whatever the practical difficulty of reaching it in time.
Substitute closures. Where an office closes on a day it selects rather than a listed holiday, that day is treated as a closure for filings made there.
Religious and observed holidays. Where a holiday falls on a weekend and is observed on another day, the observed day is normally the one that counts.
Electronic filing changes little. A system available at all hours does not make a closure day into an open one where the rule counts office days.
Check the published calendar. Most forums publish their own list, and it is the authoritative answer rather than a general holiday calendar.
Avoiding the error
Quote the rule in the diary entry. Recording days or business days alongside the date makes the assumption visible to anybody who checks it.
Count the harder way first. Working out the calendar-day date and the business-day date, and using the earlier, removes the risk on any short period.
Define it when drafting. An agreement that defines business day in its own terms avoids the whole argument before it can start.
Check the forum's holiday list. Once per year is enough, and it prevents the surprise of an unfamiliar closure.
Do not rely on software defaults. Case management systems apply whichever convention they were configured with, and the configuration is a setting rather than a rule.
Say which convention a letter uses. Correspondence that gives somebody a period should state whether it means calendar or business days, because the recipient will otherwise choose.
Leave margin on short periods. A three-day window has no room for a convention error, which is an argument for acting immediately rather than counting more carefully.
Identify the trigger first. The convention only matters once the start date is fixed, which is the exercise in when the clock actually starts.
Calendar days and business days are both in ordinary use, and the difference between them on a short period is large enough to decide whether a filing was in time.
Modern procedural codes have moved toward counting everything in calendar days, which means older habits and older commentary describe a rule that may no longer apply.
Holidays are a local question. The list that matters is the one published by the office where the step is taken, not a general national calendar.
Contracts are the least reliable place to find an answer, because they use the term business day constantly and define it rarely.
The practical protection is to record which convention was applied, to count both ways on short periods, and to act early enough that a convention error is survivable. The wording that introduces the period matters as much as the unit it is counted in, which is set out in within, by and not later than.
Points to carry away
- Short periods historically excluded weekends; many systems changed that.
- A rule that says days without qualification usually means calendar days.
- Business day definitions vary between forums and contracts.
- The error produces a plausible wrong date, which is why it survives.
- Contracts frequently use the term without defining it.
Questions readers ask
If a rule just says days, which does it mean?
In most modern procedural codes, calendar days: every day counts, including weekends and holidays, with an adjustment only if the last day falls on a closure. Older versions of several systems excluded weekends and holidays from short periods, and that history is why the assumption persists. Because the position has changed in some forums and not others, the safe method on any short period is to read the computation provision rather than to rely on what was true when somebody learned it.
Which holidays are excluded from a business-day period?
The ones recognized by the forum where the step is taken, which is usually published as a list rather than left to inference. Federal and state holiday calendars differ, an office may close for a local observance that appears on neither, and where a holiday falls on a weekend the observed day is normally the one that counts. Checking the specific forum's published calendar once a year removes the surprise, particularly around clusters of holidays at the end of the year.
What should a contract say about business days?
Define the term. An agreement that requires something within five business days without saying what a business day is has left the calendar to be argued about later, and the answer may depend on which party's location is used. A workable definition names the place, excludes weekends, and refers to the public holidays recognized there. Where the parties are in different countries, saying whose calendar governs is worth the extra clause.
Sources
- Federal Rules of Civil Procedure — Rule 6, Computing and Extending Timelaw.cornell.edu
- 5 U.S.C. 6103 — Federal Holidayslaw.cornell.edu
- Federal Rules of Appellate Procedure — Rule 26, Computing and Extending Timelaw.cornell.edu
- Federal Rules of Bankruptcy Procedure — Rule 9006, Timelaw.cornell.edu
- Office of Personnel Management — Federal Holidaysopm.gov
- Legal Information Institute — Computation of Timelaw.cornell.edu
Urban Justice Docket is a publication, not a law firm. This article states general rules and cites its sources; it is not advice about any particular case, and the law differs by state and changes over time.
More in Counting the Days
When the Clock Actually Starts Running
Every time limit has a trigger, and the trigger is defined by the rule rather than by common sense. Service, issue, receipt, demand and completion are all different events, and a period counted from the wrong one is wrong by however many days separate them. Finding the trigger in the text is the first step in any deadline question.
What a Month Means in a Deadline
A period expressed in months runs to the same day-number in the later month rather than by adding a fixed number of days. Where the later month is shorter and has no corresponding date, the period generally ends on its last day. Periods expressed in days are counted in days regardless of how many months they span, and mixing the two conventions is a common source of error.
Weekends, Holidays and Closures
Where the last day of a computed period falls on a weekend, a holiday or a day the filing office is inaccessible, the period generally extends to the next day it is open. The extension applies to the end of a period rather than to days inside it, and an office being busy, understaffed or closed to visitors is not the same as being inaccessible.