This question comes up most often with clients moving here from another state. They may be accustomed to deducting vehicle excise taxes and just assume their Florida registrations will be treated the same way. However, Florida's vehicle registration fees are usually based on weight and not the value of the vehicle. For that reason they are not deductible for Federal individual income tax purposes. The following is from the FAQ section of the IRS website.
12.7 Small Business/Self-Employed/Other Business : Income & Expenses
Are excise taxes for a vehicle deductible?
It has to be a personal property tax, not an excise tax, in order to deduct it. Deductible personal property taxes are only those based on the value of personal property such as a boat or car. The tax must be charged to you on a yearly basis, even if it is collected more than once a year or less than once a year. To be deductible, the tax must be charged to you and must have been paid during your tax year. Taxes may be claimed only as an itemized deduction on Form 1040, Schedule A (PDF), Itemized Deductions.
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Axiom Professional Group is a public accounting and consulting firm started by Joey Brannon in Bradenton, Florida. For more information you can view the Axiom Professional Group, P.A. home page or visit the Axiom web site articles page (both links will exit the blog site).