mileage or actual?

[Possi]

My client started her business using mileage on her car. 

If she gets a new car, are we allowed to change to actual expenses for the new car?

[Terry D EA]

If  you are talking about different tax years. Yes, you can change from mileage to actual expenses. I assume your client wants to do this due to the depreciation that can be claimed on the new vehicle. Always run it both ways to see which method is best.

[Lloyd Hudson]

Remember, that actual Expenses might produce a larger tax deduction one year, and the Standard Mileage might produce a larger deduction the next. If you want to use the standard mileage rate method, you must do so in the first year you use your car for business.

[Lion EA]

Each car stands alone. Each year can stand alone, if you use standard the first year.

[jklcpa]

There are a few more restrictions, mostly related to depreciation, beyond using the mileage method the first year that may disallow using mileage in future years. Tax Topic 510 gives an overview: 

https://www.irs.gov/taxtopics/tc510

[Possi]

Very helpful. Thanks, y'all!

[Abby Normal]

We almost always take mileage the first year to keep our options open. This requires you to use SL in any years of actual. One thing really nice that ATX does is calculate the depreciation component of standard mileage. So at disposition, you have the correct depreciation, even if you used actual some years and mileage in other years.

Mileage doesn't decrease when the vehicle is fully depreciated, so on a cheaper vehicle that you keep a long time, you can get something for nothing.