Connecticut Mileage Deduction 2026

Connecticut's top income tax rate is 6.99%. That is high enough that your mileage deduction carries real weight at the state level. At 15,000 business miles and a 6% effective state rate, you save roughly $653 in state taxes on top of about $4,056 federal. That is about $4,709 total.

If you run your business as an LLC or S-corp, Connecticut has a pass-through entity tax (PTET) that is now optional. It lets you pay state tax at the entity level (6.99%) and take a credit on your personal return, which can help you get around the federal $10,000 SALT deduction cap. This does not change your mileage deduction, you still deduct on Schedule C either way, but it can affect your overall state tax strategy.

How to File

Deduct on federal Schedule C, Line 9 at 72.5¢/mile. Connecticut starts with your federal adjusted gross income, so the mileage deduction flows through to your state return. Keep a mileage log with the date, destination, purpose, and miles for each trip. If you owe more than $1,000, make quarterly estimated payments.

The state does not require employers to reimburse mileage.

FAQ

Does Connecticut's pass-through entity tax affect my mileage deduction?

No. Your mileage deduction on Schedule C works the same regardless of whether you elect the PTET. The PTET is a separate strategy for managing your overall state tax liability.

Does my mileage deduction reduce Connecticut state taxes?

Yes. Connecticut starts with your federal adjusted gross income. Your Schedule C mileage deduction reduces that number directly.

Start tracking your miles for free →