Hyphenation Rules for Non-

Few questions about the prefix non- come up as often as whether it needs a hyphen. The honest answer is that usage varies by style guide, by region and by how established the resulting word has become. This page sets out the general patterns that most writers and editors follow.

The general rule: closed by default

In most modern English style guides, non- is treated as a prefix that joins directly to its base word without a hyphen, provided the result is easy to read and not confusing. This gives us closed forms such as:

nonfiction
nonsense
nonstop
nonprofit
nonexistent

These words have been in common use for long enough that readers recognise them instantly as single units, so a hyphen is unnecessary.

When a hyphen is added

There are several situations where style guides recommend keeping the hyphen:

Before a proper noun or capitalised word: a hyphen is used to separate the prefix from a name, as in non-European or non-English. Removing the hyphen here would look awkward and could cause misreading.
Before a word starting with the same letter: when non- is followed by a word beginning with n, a hyphen is usually kept for readability, as in non-native.
With newer or less common compounds: if a non- word is not yet widely established, a hyphen helps the reader parse it correctly. This is common with newer technical or social terms such as non-binary or non-compliant, where closing the word up could make it harder to read at first glance.
With multi-word bases: when the base itself is a phrase rather than a single word, a hyphen clarifies the boundary, as in non-interest-bearing.

Regional and style guide differences

Not every publication follows the same rule. Some style guides prefer hyphens more broadly across all non- compounds for consistency, while others favour closing up words as soon as they become familiar enough. Because of this, you will sometimes see the same word written both ways across different sources, such as nonprofit and non-profit. Neither form is incorrect; the choice usually comes down to the house style of the publication or organisation doing the writing.

A practical approach for everyday writing

If you are writing without a specific style guide to follow, a few simple habits will keep your usage consistent:

Default to closing the word up (no hyphen) unless there is a clear readability reason not to.
Always hyphenate before capitalised words and numerals.
Use a hyphen for newly coined or unfamiliar compounds until they become common enough to close up.
Once you choose a form for a particular word, use it consistently throughout the same document.

Checking uncertain cases

When in doubt about a specific word, a dictionary is the most reliable source, since well-established non- compounds are usually listed with their accepted spelling. For newer or more specialised terms that have not yet settled into a single accepted form, consistency within your own writing matters more than matching any particular external standard.