Section 179 deduction - how does date of placing in service affect a heavy SUV (GVWR > 6000 lbs)

[HSTX]

Trying to understand whether you get more section 179 deduction now in Jun 2025 for placing a heavy SUV for business use (you are using it about half the year but you get 40% bonus depreciation) vs placing it in service Jan 2026 (you are using it for full year but you get only 20% bonus depreciation). 

Is this deduction governed by half year or mid quarter or mid month rule?

Do you get more deduction if you use the asset for full year vs part of the year?

Anyone can help?

Thank you

HSTX

[AmeliesUncle]

No, the partial year or full year does not affect the amount of Section 179 that can be used.

Bonus Depreciation is also not affected by a partial year or full year, but as you pointed out, the percentage of Bonus Depreciation may vary from year to year (and the current bill in Congress may be changing the percentage).

Regular depreciation usually uses the half-year convention (sometimes the mid-quarter), regardless if it is used for a partial year or a full year.  If the mid-quarter rules apply, then that depends on the details.