Punctuating three uses of however

However as a conjunction (; however,)

However as an adverb (however)

However for emphasis (, however,)

The nice easy rule is semi-colon before however and comma after. But that’s not always the case . . . 

However as a conjunction

If however is joining two clauses (as a conjunctive adverb) you follow the semi-colon however comma rule. But how do you know? If you could get away with ‘and’ instead, you’re ok.

Examples

I like pizza; however, my Mum likes cheese on toast.

I like pizza and my Mum likes cheese on toast.

All however is doing is making the two ideas contrast.

However as an adverb

Sometimes however is working as an adverb of manner, in which case it requires no punctuation around it. But how do you know? If you can put in ‘in whatever way’, which is an adverb, then you’re ok.

Examples

I like pizza however it comes.

I like pizza in whatever way it comes.

Punctuation really does affect meaning

See the difference between these two examples

Examples

I like pizza; however, you arrange the topping

and

I like pizza however you arrange the topping.

(The speaker in my first example really doesn’t want to get their hands all tomatoey.)

Other conjunctive adverbs

These all follow the semicolon first comma after rule. 

Tip: don’t learn them all; just remember the ones you use. 

also 

however 

otherwise 

consequently 

indeed 

similarly 

finally 

likewise 

then 

furthermore 

moreover 

therefore 

hence 

nevertheless 

thus 

nonetheless

However for emphasis

Sometimes you can use however as an intensifier to give emphasis; then, it really does need commas either side.

Example

I, however, strongly disagree.

We, however, would never go there.