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Level 1
April 12, 2026
Question

How do I correct Cost Basis and depreciation?

  • April 12, 2026
  • 1 reply
  • 64 views

I have owned a rental house since 2017. When I started my taxes using TT last week, for some reason, TT asked me questions and seemed to forget I had this rental house. So when it asked for the cost basis, I had to go back to the paperwork of the sale. There I discovered I had previously only entered half of the cost basis and therefore I had only been taking depreciation on half the cost basis. Should I use Form 3115 to increase the cost basis to the correct amount? How do I correct this?

1 reply

Hi Palms
Level 7
April 12, 2026

You need to go back and amend your prior returns to correct your cost basis. Using an incorrect cost basis is a mathematical or posting error that cannot be corrected with Form 3115.