Timing of health insurance premium deductions

[Fish5]

In December 2019 I paid my health insurance premium for January 2020. This was an individual COBRA policy. Can I deduct that for 2020 or does than belong to 2019 since it was paid then? I know we are generally supposed to deduct the medical expenses for the year we paid them as opposed to when the service occurred (I.e. you get an X-RAY done in December, but don't get and pay the bill until January, so you claim it for the year after the service when you paid it), but this seems different. I gather for policies obtained on the Exchanges or through the ACA, which I now have, the insurance company sends you a tax form, and they seem to be deductible in the year the insurance was in effect. 

[Fish5]

Note to further clarify, I have a 1095-B showing coverage for Jan.-Nov. through COBRA and a 1095-A showing coverage in Dec. through the ACA or exchanges. I paid for the coverage for 01/20 in 12/19, but it seems more correct or consistent to count that for tax year 2020 just as I will count the premium I paid in 12/20 for 01/21 in 2021. Any comments or clarifications?

[MaryM428]

Claim the premium paid in the year that it applies to, even though you pre-paid it in December.  In particular with 1095-A, the intention is to show that you paid for insurance for the month of January, so use that month for the month your paid the premium.  

[Fish5]

Mary, thanks so much!