All kinds of problems here.
I personally purchased a new vehicle in October 2019 and used it 100% for business purposes since I use my spouse's vehicle for personal use.
Who or what entity "legally" owns the vehicle as shown on the title of that vehicle? You? Or the S-Corp?
My S Corporation reimbursed me for $18,100 of the cost since that is 100% of the Special Depreciation Allowance for 2019.
You're mixing applies and motor oil here. If the S-Corp owns the vehicle, then "you" don't get reimbursed for anything. All vehicle expenses are paid by the S-Corp - not by you personally.
If "you" own the vehicle, then the S-Corp can't claim one single penny of depreciation on that vehicle. Additionally, reimbursed expenses and depreciation have absolutely nothing to do with each other. One has no relationship to the other.
Since you purchased the vehicle in October of 2019, there is no way posssible for you to have $18,000 of deductible expenses on that vehicle for 2019. That would be $6000 a month. Even if gas was $4/gallon and you drove it 27 hours a day, 7 days a week, you could not possibly spend even $1000 a month for just gas alone.
So your post makes no sense in some aspects, and contradicts itself in other aspects. YOu need to look at your wording and try again. As it stands now, one can't even discern if what your asking about "less than 50% usage in future years" even matters. But I can tell you this about depreciation.
When you sell or otherwise dispose of the vehicle, you are required by law to recapture all prior depreciation taken and pay taxes on that recaptured depreciation in the year of sale or disposition. That recaptured depreciation is added to the AGI and has the potential to put you in the next higher tax bracket. So when it comes to the SEC 179 or Speical Depreciation ALlowance deduction, you "really" have to thank ahead. What may seem to be a little help now on the tax front, can (and usually does) become a very painful bite on the tax front later.
