Out of Hours vs. Out-of-Hours – Which is Correct?
When should you write “out of hours” or “out-of-hours”? Both forms are correct, but they serve different grammatical roles. Use “out of hours” as a phrase meaning outside normal working time; use “out-of-hours” as a compound adjective before a noun, as in “out-of-hours support.” The choice depends on grammar and position.
Out of Hours or Out-of-Hours – Which is Correct?
Both out of hours and out-of-hours are correct. The difference is grammatical rather than a matter of spelling.
Out of hours is an adverbial phrase. It usually appears after a verb or at the end of a sentence to mean “outside normal working hours.” For example: “The clinic is closed out of hours.”
Out-of-hours is a compound adjective. It comes before a noun and describes something that operates or occurs outside normal working hours. For example: “The company provides out-of-hours support.”
The hyphens help show that the three words work together as one adjective. In American English, after-hours is often more common, especially in expressions such as “after-hours service” or “after-hours trading.” However, out-of-hours is also understandable and established, particularly in professional, medical, educational, and British English contexts.
The Best Trick to Remember the Difference
Use the noun test: if the phrase comes directly before a noun and describes it, use hyphens. If it does not directly modify a noun, leave the words open.
- Before a noun: out-of-hours emergency service
- After a verb or at the end of a sentence: The service operates out of hours.
A useful swap test is to replace the phrase with after-hours. If the replacement functions as an adjective before a noun, hyphenation is usually appropriate: after-hours assistance and out-of-hours assistance.
| Word | Part of Speech | Meaning | Example |
|---|---|---|---|
| out of hours | Adverbial phrase | Outside normal working or opening hours | The helpline is available out of hours. |
| out-of-hours | Compound adjective | Describing something provided or occurring outside normal hours | We offer out-of-hours assistance. |
How to Use Out of Hours
Out of hours is an open phrase used when it functions adverbially. It commonly follows verbs such as call, operate, work, contact, and visit. It can appear in formal notices, workplace communication, customer-service messages, and everyday conversation.
The phrase normally refers to a period outside an organization’s usual schedule. Depending on the context, it may mean evenings, nights, weekends, public holidays, or any time when a business or service is normally closed.
Example 1: Please call the emergency number if you need medical advice out of hours.
Example 2: The building cannot be accessed out of hours without prior authorization.
Example 3: An automated message will direct callers to the appropriate service out of hours.
Etymology of the Phrase Out of Hours
The phrase combines the preposition out of with the plural noun hours. Out of has long been used in English to express movement beyond a limit or condition, while hours refers to scheduled periods of activity. Together, the phrase developed the practical meaning “outside the usual period of business or work.”
How to Use Out-of-Hours
Out-of-hours is a hyphenated compound adjective used before a noun. It describes services, appointments, work, access, support, care, contact, or other activities available outside standard hours.
Hyphenation is especially important when the phrase appears directly before a noun because it makes the relationship between the words clear. When the phrase follows the noun, some style guides may allow an open form, but keeping the adjective consistently hyphenated is often the clearest choice.
Example 1: The hospital has an out-of-hours medical team.
Example 2: Customers can request out-of-hours technical support.
Example 3: The landlord provided an out-of-hours contact number for emergencies.
Etymology of the Phrase Out-of-Hours
Out-of-hours developed from the open phrase out of hours. English commonly hyphenates several words when they combine to form a single adjective before a noun. The hyphens do not change the basic meaning; they simply signal that out, of, and hours function together as one modifier.
Related Concepts
Understanding compound modifiers and adverbial phrases makes the difference between these forms easier to recognize.
- Compound adjective: Two or more words that work together to describe a noun are often hyphenated when they appear before that noun. In out-of-hours service, the entire phrase modifies service.
- Adverbial phrase: A group of words that modifies a verb, adjective, or sentence is usually written without hyphens. In The service operates out of hours, the phrase modifies operates.
- Attributive position: An adjective is in attributive position when it comes before a noun. This is the position in which out-of-hours normally takes hyphens.
- After-hours: This is a common alternative, particularly in American English. It follows the same grammatical pattern: after-hours service but the service operates after hours.
Examples from Media and Literature
The following examples reflect the way the two forms appear in practical writing, fiction, and public communication:
- News reporting: A report may describe an “out-of-hours emergency department” when discussing medical provision outside standard schedules.
- Workplace communication: An employee handbook may state, “Please do not contact staff out of hours unless the matter is urgent.”
- Film and television dialogue: A character working in a hospital, hotel, or newsroom might refer to an “out-of-hours shift.”
- Public notices: A council or public agency may publish an “out-of-hours contact number” for urgent problems.
- Business writing: A company website may explain, “Messages received out of hours will be answered on the next business day.”
Practice Exercises
Choose the correct form to complete each sentence: out of hours or out-of-hours.
- The clinic provides ______ dental care at weekends.
- Please leave a message if you call ______.
- Our ______ helpline is available for urgent technical problems.
- Staff should not be expected to answer routine emails ______.
- The website lists an ______ emergency number.
Answer Key
- out-of-hours — It comes before and modifies dental care.
- out of hours — It functions as an adverbial phrase after call.
- out-of-hours — It comes before and modifies helpline.
- out of hours — It follows the verb phrase and does not directly modify a noun.
- out-of-hours — It comes before and modifies emergency number.
Out of Hours Synonyms
| Synonym | Definition |
|---|---|
| after hours | Outside the usual period of business or work. |
| outside business hours | At a time when a business is not normally open. |
| outside normal hours | Beyond the standard scheduled operating period. |
| after closing time | Following the time when a business or facility closes. |
Out-of-Hours Synonyms
| Synonym | Definition |
|---|---|
| after-hours | Available or occurring after normal business hours; commonly used as a compound adjective. |
| out-of-hours service | A service provided outside the usual schedule. |
| emergency | Available for urgent situations outside standard operating times. |
| on-call | Available to respond when needed, often outside normal working hours. |
Frequently Asked Questions
Question 1: Is “out of hours” or “out-of-hours” correct?
Both are correct. Use out of hours as a phrase, usually after a verb. Use out-of-hours as a compound adjective before a noun.
Question 2: Should “out of hours” always have hyphens?
No. Do not normally hyphenate the phrase when it functions adverbially, as in “The office is closed out of hours.” Add hyphens when it directly modifies a noun, as in “out-of-hours assistance.”
Question 3: Is “after-hours” more common in American English?
Yes. After-hours is often the more natural American English choice for a compound adjective, while out-of-hours is especially common in British and international professional English.
Question 4: Should I write “out of hours” or “outside normal hours” in formal writing?
Both are acceptable. Outside normal hours may be slightly more explicit, while out of hours is concise and widely used in workplace, medical, and customer-service communication.
Conclusion
Out of hours and out-of-hours are both correct, but they have different grammatical functions. Keep the phrase open when it describes when an action happens, as in “contact us out of hours.” Use hyphens when it comes before a noun, as in “out-of-hours contact.” Pro Tip: Correct hyphenation makes professional writing clearer and helps protect your credibility.
