English has many small spelling and usage rules that can be surprisingly confusing. One common example is the difference between “any day” and “anyday.” Because English contains many words that can be written as one word or two words depending on their meaning, it is easy to assume that both forms are correct. However, standard English generally prefers “any day” as two separate words. Understanding this small difference can make your writing clearer and more professional. Whether you are writing an email, school assignment, blog post, or everyday message, knowing the basic Grammar rule can help you avoid an unnecessary spelling mistake. Any Day vs. Anyday: The Quick Answer The standard and preferred form is “any day.” For example:
I can visit you any day this week.
We can have the meeting any day after Monday.
The package could arrive any day now.
The form “anyday” is generally considered nonstandard in modern formal English. Although you may occasionally see it in informal online writing, texting, or social media, it is better to avoid it when you want your writing to follow standard English conventions. So, if you are unsure which version to choose, remember this simple rule: Any day = correct and standard Anyday = generally nonstandard What Does “Any Day” Mean? “Any day” is a phrase made up of the determiner “any” and the noun “day.” It usually refers to an unspecified day or a day that has not been chosen yet. For example: You can come any day. This means that the person is welcome to come on whichever day they choose. Another example is: We could finish the project any day this week. Here, the exact day is unknown or flexible. The phrase can also be used when something is expected to happen soon: The baby could arrive any day now. In this sentence, “any day now” suggests that the event may happen very soon, although the exact day is uncertain. Why Is “Anyday” Usually Incorrect? The confusion comes from the way English forms compound words. Some expressions that begin with “any” are written as one word, while others remain separate. For example:
anyone
anything
anyway
anytime
Because these words exist as single words, it may seem logical to write “anyday” in the same way. However, English does not always follow a perfectly predictable pattern when forming compound words. Standard usage has retained “any day” as two words. “Anyday” may appear in informal writing, but it is generally treated as a nonstandard form rather than the preferred spelling. This is an important reminder that you cannot always create a new compound word simply by joining two familiar words together. Examples of Correct “Any Day” Usage Seeing the phrase in different situations makes the rule easier to remember. Talking About Availability I am free any day next week. This means that the speaker has no specific preference about which day is selected. You can call me any day after five. The speaker is available on any day after the stated time. Talking About Possibility The results could be announced any day now. This means the results are expected soon, but nobody knows exactly when they will be announced. The weather may change any day. The sentence expresses a possibility without identifying a particular day. Talking About Choice You can choose any day for the appointment. Here, the person has freedom to select whichever day works best. We can travel any day during the holiday. Again, the phrase indicates flexibility. “Any Day” in the Expression “Any Day Now” One of the most common expressions containing these words is “any day now.” This expression means that something is expected to happen very soon. For example: The new store should open any day now. The speaker expects the opening to happen soon but does not know the exact date. Another example is: My package should arrive any day now. The delivery is expected shortly. In these expressions, “any day” remains two words. Writing “anyday now” is not the standard form. Any Day vs. Every Day Another reason people make this mistake is confusion with “everyday” and “every day.” These expressions are different. Every day means each day: I walk to work every day. Here, “every day” refers to something that happens on each day. Everyday, however, is an adjective meaning ordinary, usual, or routine: These are my everyday shoes. The word “everyday” describes the shoes as ordinary or commonly used. This distinction does not mean that “anyday” should be treated in the same way. Standard English uses “any day” when referring to an unspecified day. Any Day vs. Anytime “Any day” can also be confused with “anytime.” Both expressions have their own usage patterns. Consider: Call me anytime. Here, “anytime” means whenever or at any time. But: Do you have any time to talk? In this sentence, “any time” refers to an amount or period of time. The distinction can be confusing because “anytime” is accepted as a word in many forms of English, while “anyday” has not developed the same standard status. Therefore, it is better not to assume that every “any + noun” combination can be joined together. Common Mistakes With Any Day Here are some examples of mistakes that writers commonly make. Incorrect: I can meet you anyday. Correct: I can meet you any day. Incorrect: The delivery should arrive anyday now. Correct: The delivery should arrive any day now. Incorrect: You can visit us anyday this month. Correct: You can visit us any day this month. Incorrect: We can schedule the appointment anyday next week. Correct: We can schedule the appointment any day next week. Using the two-word version consistently is the safest choice, particularly in professional, academic, and formal writing. Why Word Spacing Matters A single space can sometimes change how a phrase functions in English. Writers often overlook spaces because the spoken pronunciation of “any day” and the written form “anyday” may seem almost identical. However, written English depends on standard word forms and established usage. Correct spacing makes your writing easier to understand and signals that you are familiar with conventional English. This is especially important in professional communication. A small mistake may not completely change the meaning of a sentence, but repeated mistakes can make writing appear less polished. How to Remember the Correct Form A simple trick can help you remember the difference. Think about the actual meaning of day. If you can replace the phrase with “any particular day” or “whichever day,” use “any day.” For example: You can visit any day. You can also think: You can visit on whichever day you choose. The meaning remains clear, so “any day” should stay as two words. Another useful memory trick is to remember: Any day = a day Anyday = avoid it in standard writing This simple rule works in most situations. Is “Anyday” Ever Used? You may encounter “anyday” online, particularly in informal posts, comments, messages, or user-generated content. Some writers use it because they believe it is a natural compound word, while others simply type it without thinking about the spelling. Seeing it online does not necessarily mean that it is the preferred standard form. If you are writing casually to friends, people may understand “anyday” without difficulty. However, when writing an article, assignment, business email, website content, application, or other formal material, “any day” is the better choice. Final Verdict: Any Day or Anyday? The answer is straightforward: use “any day” as two words. “Any day” is the standard phrase used when talking about an unspecified day, a flexible choice of days, or something that could happen soon. It works naturally in both casual and formal English. “Anyday” may occasionally appear in informal writing, but it is generally considered nonstandard and is best avoided when accuracy matters. Remember these examples:
