How do I book annual insurance costs that are billed on an annual basis but are paid either monthly or quarterly?

Actually, if you pay it monthly, you can just expense it each month as you go.

If you wanted to get really technical, you do have the liability and likely it is not something you can get out of. So you could record the liability and put the whole thing in prepaid insurance, expensing one month as an adjusting entry as you go. Even though you haven't 'prepaid' it, they kind of already have the obligation of the coverage too.

However, since monthly statements aren't really the most important ones, I don't think that's necessary. That's a little bit opinion there.