I bought a truck for my business for 4900 in 2024. I used it for only business for 2024 and took the full $4900 as a section 179 deduction.

[timothybpayne]

In 2025, the use for business fell below 50% for the truck, so I need to calculate the recapture. How should lines 33-35 on form 4797 be filled out?

[DianeW777]

The total section 179 amount should be entered on line 33(a), or $4,900.  

1. Vehicles are generally treated as 5-year property under MACRS for business, allowing depreciation over 6 years due to the half-year convention (20%, 32%, 19.2%, 11.52%, 11.52%, 5.76%).
2. Half-year convention assumes you purchased the vehicle before October, 2024 (before the last quarter).

The recomputed depreciation will be the following converted from the regular method to the straight line method due to the reduction of 51% or less business use:

• 2024 = $4,900 x 10% = $490
• 2025 = $4,900 x business use percentage x 20% = $  | Combined Total = $____ this will be the amount on line 34(a)
  • IRS Publication 946 - SLHY Convention Table

The business use percentage is business miles divided by total miles on the vehicle. Line 35a will be the difference.

@timothybpayne

[Edited: 03/02/2026 | 3:57 PM PST]

[AmeliesUncle]

Vehicles with 50% or less use would use Straight-Line depreciation.  That means in the other person's answer, the first year would be 10%, not 20% (assuming it used the Half-Year convention).