If you pay insurance premiums in advance which year do you deduct the expense?

If you  pay your insurance premium (business)  early when the bill arrives in December but  insurance  applies to the next tax year, which year do you deduct the expense if you are  cash basis taxpayer ? Do you deduct the expense the year you pay it or the year it applies to ?  I know there are rules about... show more If you  pay your insurance premium (business)  early when the bill arrives in December but  insurance  applies to the next tax year, which year do you deduct the expense if you are  cash basis taxpayer ? Do you deduct the expense the year you pay it or the year it applies to ? 

I know there are rules about prepaying expenses to get a deduction.  In the past I only deducted the yearly premium.     I've already paid the 2017  insurance premiums in full via 4 quarterly installments .   The coverage runs through Jan  15, 2018.  I'm not trying to claim an extra deduction.  I would like to know if I can save the expense  till next year even though it was paid in Dec 2017 or am I required to claim the extra payment in  2017  ?   I also don't want to risk an audit by having a larger insurance expense than I normally deduct.   Thank You.
Update: Thank you Casey but I'm looking for help from a tax specialist. I will not be able to pay bills the first two weeks of January. I just mailed and then remembered something I read about prepaying taxes and insurance as well as prepaid rent. It explains why you can't but doesn't tell me what to do if... show more Thank you Casey but I'm looking for help from a tax specialist. I will not be able to pay bills the first two weeks of January. I just mailed and then remembered something I read about prepaying taxes and insurance as well as prepaid rent. It explains why you can't but doesn't tell me what to do if you did. I know there are exceptions even with cash basis taxpayers.
Update 2: My understanding is you deduct those type of expenses in the year they apply to no matter if you use cash or accrual. Please correct me if I'm in error.
Update 3: If you are correct Casey, how can I deduct an expense if its not deductible in that tax year ?
Update 4: I know both NA and Judy are both tax pro's from reading this forum off and on. NA gives nothing away free :) I appreciate the fact NA wants me to prove it to myself or when someone else provides a link to back up what they say. I'm not going to take the word of just anyone here. Ok Chapter 6... show more I know both NA and Judy are both tax pro's from reading this forum off and on. NA gives nothing away free :) I appreciate the fact NA wants me to prove it to myself or when someone else provides a link to back up what they say. I'm not going to take the word of just anyone here.

Ok Chapter 6 Insurance 'Prepayment'

Cash method.
If you use the cash method of
accounting, you generally deduct insurance
premiums in the tax year you actually paid
them, even if you incurred
Update 5: them in an earlier year. However, see Prepayment , later. Prepayment. You can't deduct expenses in advance, even if you pay them in advance. This rule applies to any expense paid far enough in advance to, in effect, create an asset with a useful life extending substantially beyond the end... show more them in an earlier
year. However, see
Prepayment
, later.

Prepayment.
You can't deduct expenses in
advance, even if you pay them in advance. This
rule applies to any expense paid far enough in
advance to, in effect, create an asset with a
useful life extending substantially beyond the
end of the current tax year.
Expenses such as insurance are generally
allocable to a period of time. You can deduct in­
surance expenses for the year to which they are
allocable.
Update 6: I recall reading the info in that pub years ago and that must be why it stuck in my mind. Paying insurance through April 15, 2018 in Dec, due Jan 15, 2018 (substantial asset?) As for insurance, if I'm interpreting the info correctly, even tho I'm cash basis tax payer, I can deduct it in 2018 - the year... show more I recall reading the info in that pub years ago and that must be why it stuck in my mind.

Paying insurance through April 15, 2018 in Dec, due Jan 15, 2018 (substantial asset?)

As for insurance, if I'm interpreting the info correctly, even tho I'm cash basis tax payer, I can deduct it in 2018 - the year it applies.
Update 7: I realize I didn't specify what type of business insurance. It's property insurance not health.
Update 8: I mean No disrespect to accountants. If I want someone to do my books, I'll hire an accountant or cpa. Unless the CPA is also a tax specialist, I'm not having them prepare my taxes anymore than I would use the services of an attorney who is not tax attorney or specifically trained.. Whenever I've... show more I mean No disrespect to accountants. If I want someone to do my books, I'll hire an accountant or cpa. Unless the CPA is also a tax specialist, I'm not having them prepare my taxes anymore than I would use the services of an attorney who is not tax attorney or specifically trained.. Whenever I've used the services of tax pro emphasis on pro, I've never had them audit my books.
Update 9: * audit my books ... do the bookkeeping.
Update 10: Well Max, I know you are tax pro also. According to Pub 535, it says 'generally' you do so if you are a cash basis tax payer. There seems to be exceptions. When it comes to prepaid insurance it states you deduct insurance in the year it applies to even if it is not a substantial asset being insurance is... show more Well Max, I know you are tax pro also. According to Pub 535, it says 'generally' you do so if you are a cash basis tax payer. There seems to be exceptions. When it comes to prepaid insurance it states you deduct insurance in the year it applies to even if it is not a substantial asset being insurance is based on a period of time. I'm paid up to Jan 15, 2018. The payment I just made is for 2018. Why are both you &Judy saying different when I provided the facts before NA linked the pub?
Update 11: Thank you @tro

@Bostonian Thanks for clearing up the confusion. I appreciate it ! You're saying the substantial asset rule must apply first and when I read it again, .sounds right. Guess I'll need to make a habit of paying the bill in Dec from now on.
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