I use a personal vehicle for business purposes and use the standard mileage deduction. I had an accident during a business trip. Is the deductible for the claim tax deductible?
As a general rule, you must choose between a mileage deduction or an actual expenses deduction. The idea is that the mileage deduction is supposed to cover all costs of using the car. Exceptions include parking fees and tolls, which can be deducted separately under either method. You explicitly cannot deduct insurance costs if you claim a mileage deduction.
Separately, you probably won't be able to deduct the deductible for your car as a casualty loss. You first subtract $100 from the deductible and then divide it by your Adjusted Gross Income (AGI) from your tax return. If your deductible is over 10% of your AGI, you can deduct it.
Note that even with a $1500 deductible, you won't be able to deduct anything if you made more than $14,000 for the year. For most people, the insurance deductible just isn't large enough relative to income to be tax deductible.