So I ran a test to see what was happening. First I entered a vehicle into service in 2022 two different ways, with standard 5 yr depreciation and with first year bonus depreciation. I manually calculated the depreciation for each way for 3 years (2022, 2023 and 2024) and compared that to what Turbo Tax calculated. Everything matched for all 6 variations.
Then I entered the same vehicle into service in 2023 two different ways, with standard 5 yr depreciation and with first year bonus depreciation. Again I manually calculated the depreciation for each way, but only for 2 years (2023 and 2024) and compared to what Turbo Tax calculated. 3 out of 4 matched. The one that didn't match was the second year (2024) depreciation when bonus was taken in year 1 (2023). It still calculates to $2,790 when the manual calculation comes to $8,781. The tax law hasn't changed and the only thing different is the max limit for bonus increased from $19,200 to $20,200.
I think the 2024 version of Turbo Tax has an error that needs to be updated. See my chart below for all calcs.
| Depreciation Analysis | | | | | | | | | | | |
| | | | | | | | | | | | |
| Purchase Price | $54,500 | | | | | | | | | | |
| Business Use | 80% | | | | | | | | | | |
| | | | | | | | | | | | |
| | Proposed Calculation | Est Value | Turbo Tax Calculated | | Proposed Calculation | Est Value | Turbo Tax Calculated | | Proposed Calculation | Est Value | Turbo Tax Calculated |
| | | | 2022 | | | | 2023 | | | | 2024 |
| First Year Standard Dep | | | | | | | | | | | |
| | $54,500 x 80% x 20% | $8,720 | $8,720 | | $54,500 x 80% x 32% | $13,952 | $13,952 | | $54,500 x 80% x 19.2% | $8,371 | $8,371 |
| | | | | | | | | | | | |
| First Year Bonus Dep | | | | | | | | | | | |
| | Max $19,200 x 80% | $15,360 | $15,360 | | ($54,500 x 80% ) -$15,360 | $9,037 | $9,037 | | $28,240 x 19.2% | $5,422 | $5,422 |
| Bonus Max = $19,200 | | | | | 28240 x 32% | | | | | | |
| $19,200 x 80% = $15,360 | | | | | | | | | | | |
| | | | | | | | | | | | |
| | | | | | Proposed Calculation | Est Value | Turbo Tax Calculated | | Proposed Calculation | Est Value | Turbo Tax Calculated |
| | | | | | | | 2023 | | | | 2024 |
| | | | First Year Standard Dep | | | | | | | | |
| | | | | | $54,500 x 80% x 20% | $8,720 | $8,720 | | $54,500 x 80% x 32% | $13,952 | $13,952 |
| | | | | | | | | | | | |
| | | | First Year Bonus Dep | | | | | | | | |
| | | | | | Max $20,200 x 80% | $16,160 | $16,160 | | ($54,500 x 80% ) -$16,160 | $8,781 | $2,790 |
| | | | Bonus Max = $20,200 | | | | | | $27,440 x 32% | | |
| | | | $20,200 x 80% = $16,160 | | | | | | | | |
| | | | | | | | | | | | |
