We placed our home in service in 2014 with 25% business use because 25% of the home was rented, and used 25% of the cost basis of the home as the amount reported on form 4562. In 2015, we placed an additional 25% of the home in service, so the total business use is now 50%.

Do we need to submit an additional form 4562 for the additional 25% percent increase in the cost basis, or do we just increase the depreciation amount on Sched E without submitting an additional 4562?

We placed our home in service in 2014 with 25% business use because 25% of the home was rented, and used 25% of the cost basis of the home as the amount reported on form 4562. In 2015, we placed an additional 25% of the home in service, so the total business use is now 50%. =====>Correct; you need to depreciate on ly 25% of the home in rental service for 2014 and 50% for 2015.

Do we need to submit an additional form 4562 for the additional 25% percent increase in the cost basis, or do we just increase the depreciation amount on Sched E without submitting an additional 4562?======>if you fill in your asset entry worksheet then you simply change biz use percentage then the change of percentage of biz use ?d be applied to your SCh E of 1040 line 18 and part 3 line 17 on f 4562

Thanks Wnhough! Can you confirm that I also place in service 25% cost basis on part 3 line 19h on f4562 for 2015? Or do I put 50% cost basis on line 19h? I will include the 2014 amount on part 3 line 17.

now you are filign 2015 return NOT 2014 return and as In 2015, you placed an additional 25% of the home in service, so the total business use is now 50%, you need to report the depre amt on 50% use