Mileage deduction for 1099-NEC income

[planphore]

My daughter who is self employed has been using her personal vehicle for business purposes since 2022.  She only recently discovered she can write off mileage as a business expense.  

When trying to enter the mileage, TT asks "When did you start using the vehicle for work? Note this date is sometimes from a prior year which is okay to enter."

If I enter a 2022 date, there is no change in the tax due.  If I enter  Jan 01, 2024, a substantial reduction in the tax due/refunded results. Change it back to the 2022 date, and the amount of tax due goes up, equal to the value before I entered any mileage expense.

It seems like TT is ignoring the expense if the vehicle use commenced prior to 2024

Appreciate some help in understanding why the software is doing this and how to help my daughter take advantage of this tax provision

[AnnetteB6]

If you go all the way through the vehicle expense section, keeping the earlier date, then there will be a question that asks whether the standard mileage or actual expense method was used in the first year that the car was used for business.  The answer to that question affects whether the standard mileage rate can be claimed in later years.  That is why you may not be seeing any expenses included when you answer with the 2022 start date.

Then, when you change the start date to 2024, the program is assuming that 2024 is the first year of business use.  Therefore, you can choose which method to use for the expenses and not be constrained by the method used in an earlier year.  

So, even though she has been using the vehicle for business purposes since 2022, if 2024 is the first year that any expenses are being claimed on the tax return, enter the start date as a day in 2024.