“anytime” vs. “any time”
Use "anytime" as a single-word adverb meaning whenever, and use "any time" as two words whenever the phrase follows a preposition like "at" or refers to a quantity or amount of time.
anytime
"Anytime," one word, functions as an adverb meaning whenever, at any point without restriction ("call me anytime"). It's a relatively modern fusion, becoming widely accepted as a single word mainly over the 20th century, following the same general pattern as other compound time-adverbs like "anywhere" and "anyhow."
any time
"Any time," two words, is simply the word "any" modifying the noun "time," most often appearing after a preposition like "at" ("at any time") or in comparative constructions ("any time you'd like," "more than any time before"). Because it's built from two ordinary, separately meaningful words, it has never fully lost its two-word status the way "anytime" has.
The real distinction
The reliable test: if the phrase directly follows a preposition, especially "at," you almost always need the two-word "any time" ("at any time," "at any time of day"), since "anytime" as a single adverb doesn't grammatically follow prepositions the way a noun phrase does. If the phrase stands alone as an adverb describing when something can happen, with no preceding preposition, the one-word "anytime" works fine and is now the more common, casual choice ("call anytime"). Some style guides are stricter than others here: many treat "anytime" as fully acceptable in all but the most formal writing, while a few holdout style guides still prefer "any time" as two words in every case, treating "anytime" the way "alright" is treated — as an informal variant rather than a fully standard one. Unlike "alright," though, "anytime" has achieved considerably wider acceptance in mainstream dictionaries and everyday professional writing, making it a much safer choice than "alright" even in reasonably formal contexts. A useful secondary test specific to this pair: try inserting a specific number or amount into the phrase, such as "any amount of time" — if that expanded version fits the sentence's meaning, you need the two-word "any time," since you're describing an amount or quantity of time rather than simply describing when something occurs. Customer service and scheduling writing offers a clean illustration of the split: "you can call anytime" reassures a customer that no specific hour is required, while "you can cancel at any time" describes a right that exists throughout a duration or contract period — both sentences are correct, but only because each correctly matches its own grammatical pattern, general adverb versus prepositional phrase, rather than because the two spellings are freely interchangeable. Subscription services, warranties, and policy documents lean particularly hard on the two-word "any time" for exactly this reason, since the phrase there is functioning as a genuine noun phrase describing a span or point within a defined period, not as a casual adverb describing an open-ended invitation the way "call anytime" does.
Examples with “anytime”
- Feel free to call anytime after five o'clock.
- You can stop by the office anytime this week.
- She said we could visit anytime we wanted.
- The store is open anytime between nine and nine.
- He's available to talk anytime, day or night.
- Drop off the package anytime before Friday.
- The offer is valid anytime during the sale.
- You can reschedule the appointment anytime that works for you.
Examples with “any time”
- At any time, the manager can approve the request.
- She hasn't had any time to relax this week.
- This is busier than any time I can remember.
- We don't have any time left before the deadline.
- You may cancel the subscription at any time.
- He hasn't taken any time off in over a year.
- The alarm can go off at any time of night.
- There wasn't any time to review the contract carefully.
Memory trick
Check whether a preposition like "at" sits right before the phrase — if so, keep it as two words, "any time." If the phrase stands alone describing when something can happen, with nothing before it, the fused "anytime" works fine in almost all but the most formal writing. A further check: if you could insert "amount of" into the phrase ("any amount of time") and it still makes sense, you're describing a quantity, so keep it as two words.