Tax Year Prior to 2020: How to change life of depreciable asset

[euphoriant]

I used TurboTax desktop last year and I just purchased TurboTax desktop for this year (2018) and I was reviewing the information that it imported when I noticed that TT (or I) depreciated various assets, one of them being an air conditioner installed on a residential rental property for 39 years when it should have been 27.5 years.  How do I correct this?

[KarenL]

You will need to amend your 2017 tax return.  Please see the the instruction on how to do this here "How to amend (change or correct) a return you already filed" 

Amending is done on Form 1040X and it will only show the difference in the amount owed after you made the adjustment.  

Also, amended returns have to be printed and mailed.  It may take up to 12 weeks to process.