@wlifrye wrote:
I had surgery in December 2018. I didn't get / pay the bills until 2019. Can I still deduct these expenses on my 2018 taxes?
No. As a cash basis taxpayer, you report expenses in the year they are actually paid (in this case that would be 2019).
See https://www.irs.gov/publications/p502#en_US_2018_publink1000178852
