401k contributions reduce modified AGI, the maximum contribution for 2023 is $22,500 so you could get below the 300k mark with 401k alone. HSA contributions also reduce modified AGI.
If you take delivery of the vehicle in 2023 you could also use 2022's modified AGI to qualify per IRS:Credits for New Clean Vehicles Purchased in 2023 or After:
To qualify, you must:
- Buy it for your own use, not for resale
- Use it primarily in the U.S.
In addition, your modified adjusted gross income (AGI) may not exceed:
- $300,000 for married couples filing jointly
- $225,000 for heads of households
- $150,000 for all other filers
You can use your modified AGI
from the year you take delivery of the vehicle or the year before,
whichever is less. If your modified AGI is below the threshold in 1 of
the two years, you can claim the credit.
Note that it's modified AGI for the credit, check the IRS documentation to see if any modifications to your AGI apply:
There are some headlines indicating the credit might be easier to qualify for in 2024, but nothing official yet that I've seen. Since it's nearing the end of the year it's worth looking to see if anything is different for your state between 2023 and 2024 regarding EV credits, for example Colorado is increasing there maximum potential EV credit.