There is no reliable difference in meaning: both mean "in spite of that". "It rained all week; nevertheless, we finished the roof." "The pay is poor; nonetheless, she loves the job." Swap them in either sentence and nothing changes. Choose on rhythm, not rules.
The honest answer first
Major dictionaries define each word using the other. No usage authority sets out a rule separating them, and no careful writer is following one. Anyone who tells you nonetheless is wrong in a given sentence is stating a preference.
Two tendencies are worth knowing, but neither is binding:
- Nevertheless is more frequent in published English, and slightly more formal in feel.
- Nonetheless is sometimes preferred where degree or quantity is in play — "the sum was small; nonetheless, it made a difference" — because none the less literally means "not any less". This is a faint pull, not a requirement.
How to use either one
Both are conjunctive adverbs. They connect two independent statements while signalling contrast, and they carry a punctuation obligation that trips people up more often than the word choice does.
- Full stop: "The evidence was thin. Nevertheless, the case went to trial."
- Semicolon: "The evidence was thin; nonetheless, the case went to trial."
- Mid-sentence, with commas: "The case, nevertheless, went to trial."
What you cannot do is join two clauses with a comma alone: "The evidence was thin, nevertheless the case went to trial" is a comma splice.
The test
Substitute even so. If "even so" fits, both words fit, and you can pick whichever reads better aloud. If "even so" does not fit, you probably want a different connector altogether — however, still, all the same or despite that.
Choosing between them in practice
Read the sentence out. Nevertheless has four syllables and a heavier landing; nonetheless has three and moves faster. In a long sentence already crowded with clauses, nonetheless is often kinder to the reader. At the start of a paragraph making a firm turn, nevertheless has more weight.
Neither should appear twice in a paragraph. If you find yourself reaching for one repeatedly, the underlying problem is usually too many contrasts stacked together — cut one.
Spelling
Both are single words in modern English. None the less as three words survives in British writing but looks dated and is often mistaken for an error; never the less as three words is simply wrong. Write them closed up.
The one place they differ
Nonetheless occasionally appears in the older phrasing "none the less for it" — "he was none the less determined for the setback" — where it functions as a comparative rather than a connector. Nevertheless cannot do that job. It is a small corner of usage, but it is the only genuine split between the two.
Frequently Asked Questions
Is nonetheless less formal than nevertheless?
Only marginally, and not in a way readers register. Both belong to careful writing; neither would be out of place in an academic paper or a broadsheet. Nevertheless is simply the more common of the two.
Can I start a sentence with nevertheless?
Yes, and it is one of the word's most natural positions: "Nevertheless, the plan went ahead." Follow it with a comma. The same goes for nonetheless.
Is 'none the less' as three words wrong?
Not wrong, but dated. It survives in British usage and in the construction "none the less for it". For the ordinary connective sense, write nonetheless as one word.