Any Day vs. Anyday: Which One Is Correct?

English is full of small spelling and usage questions that can make even experienced writers stop and think. One common example is “any day” vs. “anyday.” The two forms look almost identical, but there is an important difference between them. If you are writing an email, school assignment, blog post, business document, or social media caption, choosing the standard form can make your writing clearer and more professional.

The correct form in standard English is “any day”, written as two separate words. The word “anyday” is generally considered nonstandard and is best avoided in formal writing. Major dictionaries such as Collins and Dictionary.com list and explain “any day” as the standard expression.

Any Day vs. Anyday: The Quick Answer

If you are wondering which spelling to use, the simple answer is:

Correct: I can meet you any day next week.

Incorrect or nonstandard: I can meet you anyday next week.

“Any day” is used when you are talking about an unspecified day or saying that the exact day does not matter. For example, if someone asks when they can visit you and you are flexible, you might say, “You can come any day.”

The two words work together as a phrase, with “any” modifying the noun “day.” This is why keeping them separate is the safest choice.

What Does “Any Day” Mean?

The phrase “any day” can have several closely related meanings. Usually, it refers to an unspecified day, a day of someone's choice, or a time in the near future.

For example:

You can call me any day this week.
We can meet any day that works for you.
She could arrive any day now.
I would choose this restaurant over the other one any day.
Any day is fine for the appointment.

Dictionary.com explains “any day” as referring to no particular time, while Collins also gives the meaning of something that may happen sometime within the next several days.

The exact meaning depends on the sentence, but the spelling remains the same: any day.

Why Is “Anyday” So Common?

It is easy to understand why people write “anyday.” English contains many common words that combine “any” with another word.

For example, we have:

anyone
anybody
anything
anywhere
anytime

Because “anytime” is commonly written as one word, people naturally assume that “anyday” should work in the same way. However, English does not always follow a perfectly consistent pattern when words become compounds.

The standard form is “any day.” Wiktionary describes “anyday” as a nonstandard form of “any day,” while Grammar https://residencehexa.com/any-day-vs-anyday/ also recommends keeping the two words separate, especially in formal writing.

Any Day in Everyday Sentences

Understanding real examples is one of the easiest ways to remember the correct form.

Consider these sentences:

I can visit you any day next week.

Here, the speaker does not have a specific day in mind. Monday, Tuesday, Wednesday, or another day could work.

The package should arrive any day now.

In this sentence, “any day now” means that the package is expected very soon, although the exact day is unknown. Oxford also recognizes “any day now” as an expression meaning very soon.

You can choose any day for the meeting.

The person has freedom to select whichever day is convenient.

I would take a quiet evening at home any day.

Here, “any day” expresses a strong preference.

These examples show that “any day” is useful in many different situations.

“Any Day Now” Is Always Two Words

One of the most common expressions containing “any day” is “any day now.” It means that something is expected to happen very soon, although the exact moment is uncertain.

For example:

The results could be announced any day now.

We expect the delivery any day now.

The baby could arrive any day now.

This expression is widely recognized in standard English. Collins defines “any day now” as something that will happen sometime in the next several days, while Oxford gives it as an informal expression meaning very soon.

Writing “anyday now” is therefore best avoided.

Is “Anyday” Ever Acceptable?

You may occasionally see “anyday” written as one word, particularly on social media, in informal messages, or in user-generated content. Some people use it casually in phrases such as:

I would choose pizza anyday.

However, the fact that a form appears online does not necessarily mean it is standard English. “Anyday” is generally treated as a nonstandard spelling rather than the preferred form.

If you are writing something important, the safest approach is to use “any day.” This is especially true for academic assignments, professional emails, websites, articles, resumes, and formal documents.

Any Day vs. Anytime

Another reason people become confused about “any day” is the word “anytime.”

“Anytime” is an accepted word, particularly in American English, and it can mean “at any time” or “whenever.” Dictionary.com lists “anytime” as an adverb.

For example:

Call me anytime.

But this does not automatically mean that “anyday” should also be written as one word.

Compare:

Call me anytime.

Call me any day.

The first uses “anytime” as an adverb. In the second, “any” directly modifies the noun “day.” Merriam-Webster explains a similar distinction with expressions such as “any time” and “every day,” showing that English compound-word patterns are not always predictable.

A Simple Trick to Remember the Difference

If you are unsure whether to write “anyday” or “any day,” try replacing the phrase with “any particular day.”

For example:

I can meet you any day next week.

You could think of it as:

I can meet you on any particular day next week.

Because “day” is functioning as a noun, keeping “any” and “day” separate makes sense.

Another useful trick is simply to remember this rule:

Any + day = any day

This works for common expressions such as:

any day this week
any day next month
any day of the week
any day now
on any day
choose any day
Common Mistakes to Avoid

Here are a few mistakes that are easy to make:

Incorrect: I can come anyday.

Correct: I can come any day.

Incorrect: The letter should arrive anyday now.

Correct: The letter should arrive any day now.

Incorrect: You can select anyday that suits you.

Correct: You can select any day that suits you.

Making this small correction can improve the clarity and professionalism of your writing. Good Grammar is not always about complicated rules; sometimes it simply means recognizing which form is standard and using it consistently.

Final Verdict: Any Day or Anyday?

When choosing between “any day” and “anyday,” use “any day.” It is the standard form for referring to an unspecified day, a day of someone's choice, or something that may happen soon.

Any day = standard and preferred

Anyday = nonstandard and generally best avoided

The phrase may seem like a tiny detail, but using the correct form helps your writing look polished and natural. Whether you are writing an academic paper, professional message, blog article, or everyday conversation, choosing the standard expression is always a good habit.