It seems that you're using the online Free edition of Turbo Tax, and the Free edition doesn't include Schedule A used for itemized deductions, which you would need to claim a mortgage interest deduction. If however, you're really using one of the other editions, go to Federal, then Deduction and Credits, and finally Mortgage Interest, Refinancing, and Insurance. You'll be asked a series of questions about your mortgage and refinancing if any.
Have a look at this as well: https://ttlc.intuit.com/questions/1899651-what-kinds-of-refinancing-costs-can-i-deduct
And: https://ttlc.intuit.com/questions/1901495-can-i-deduct-mortgage-points
I don't want to use the refinance question feature because the loan closed on 12/12 but the loan term doesn't start until 01/01, which is when the amortization should start.
Does TurboTax have an official answer for this? I think their answer is 163, but I've read both 163 and 461 and I don't see where refinance closing costs are covered. It shouldn't be that difficult to get an answer.
No, TurboTax does not have an official answer. There are probably several options; however, Section 163 is not right. That deals ONLY with Interest.
Intuit's unofficial answer is 446. That is okay, but many very experienced tax experts prefer 461 over 446 (461 uses 446 as a starting point). Regulation 1.461-1 says "If an expenditure results in the creation of an asset having a useful life which extends substantially beyond the close of the taxable year, such an expenditure may not be deductible, or may be deductible only in part, for the taxable year in which made."
That basically says the general rule is the costs need to be spread out.
Other options are 263 and 162. Regulation 1.263(a)-4 deals with capitalizing Intangibles. Section 162 is deducting business expenses.