Most business owners think the car is a write-off because they use it for work sometimes.
The IRS thinks in percentages, methods, and proof.
Vehicle and mileage deductions are real. They also get butchered: commuting claimed as business miles, no log, mixing personal trips, or picking the wrong method and hoping software cleans it up in April.
You don't need to become a fleet accountant. You need one clear method, honest business-use percentage, and a habit light enough that you'll actually keep it.
What you can (and can't) deduct
Usually deductible (business portion):
- Miles driven for clients, job sites, suppliers, networking that is clearly business
- Parking and tolls for business trips
- Under the actual expense method: gas, repairs, insurance, registration, depreciation or lease payments, allocated to business use
Usually not deductible:
- Normal commuting from home to your regular workplace
- Personal errands, even if you take a work call in the car
- "I might post about it later" miles with no business purpose
Commuting is the trap. Driving from your house to the office you go to every day is personal under the rules, even if you listen to a business podcast the whole way.
Example: An agency owner drives 12,000 miles a year. About 4,800 are client meetings and supply runs. 7,200 are home-to-office and personal. They claim 100% business use because "the car is for the company." That's not strategy. That's an audit story waiting for a soundtrack.
Two methods: pick one lane
For most owned cars used in business, you're choosing between standard mileage and actual expenses. You don't freestyle both for the same vehicle in ways the rules don't allow. Get the first-year choice right with your advisor.
Standard mileage rate
You multiply business miles by the IRS rate for that year. Simpler recordkeeping. You still need a mileage log. Some actual costs (like business parking and tolls) can still stack on top depending on the year and your facts.
Actual expenses
You track what the car really cost, then multiply by business-use percentage. More work. Sometimes more deduction if the car is expensive to run and business use is high. Depreciation and lease rules get picky fast, especially with heavier vehicles and listed property rules.
| Factor | Standard mileage | Actual expenses |
|---|---|---|
| Main input | Business miles × IRS rate | Real costs × business-use % |
| Recordkeeping | Strong mileage log | Log + receipts for car costs |
| Best when | You want simple and miles are the story | High costs and high business use |
| Watch-outs | First-year elections and limits | Depreciation caps, personal use |
| Commuting | Still not business miles | Still not business use |
Neither method invents a deduction for personal driving. They only price the business slice.
The log is the product
Not knowing your numbers is like driving without GPS. Same idea with the car: if you can't show business miles, you don't have a clean deduction.
A usable log has, at minimum:
- Date
- Miles (or odometer start/stop)
- Where / why (client, job site, purpose)
- Business vs personal for the trip
Apps are fine. A notes app is fine. A reconstructed "I definitely drove a lot" spreadsheet in March is how deductions shrink.
Do it weekly if you can. Monthly at worst. Waiting until tax season is how fiction enters the return.
Mistakes that kill the write-off
1. Calling commuting "business."
Home to regular office doesn't magically become deductible because you have an LLC.
2. 100% business use with a family car.
If kids get dropped at school in it, say so. Honest 60% beats fake 100% every day of the week.
3. No contemporaneous log.
Memory is not a recordkeeping system. Publication 463 is clear that you need evidence.
4. Mixing methods carelessly.
Switching approaches without understanding the rules can lock you out of options or create a mess on depreciation.
5. Forgetting the books.
The car deduction sits on top of clean bookkeeping. If personal charges and business costs are scrambled, your vehicle percentage is a guess.
6. Buying a truck for the TikTok, not the job.
Heavy vehicle rules and Section 179 conversations are real for the right businesses. They're not a personality purchase with a tax hashtag. Facts first. Marketing second.
Home office and the car (don't double-confuse yourself)
A qualified home office can change what counts as commuting in some situations, because your principal place of business may be home. That does not mean every drive is deductible. It means the map of "regular workplace" can look different. Get that reviewed before you rewrite your whole mileage story.
Side-by-side: weak claim vs. defendable claim
| Factor | Weak claim | Defendable claim |
|---|---|---|
| Business use | "Basically all of it" | Percentage from a real log |
| Commuting | Included | Excluded |
| Method | "Whatever saves more in April" | Chosen with rules + first-year awareness |
| Proof | Bank charges for gas | Miles + purpose + (if actual) receipts |
| Personal use | Ignored | Tracked and removed |
| Advisor conversation | Never | Reviewed with tax planning |
Who this is for (and who should keep it simple)
This is for you if:
- You drive for clients, sites, or business errands regularly
- You've been "estimating" miles for years
- You bought or leased a vehicle partly for the business and never set a method
- You want the deduction without the audit headache
Keep it lighter if:
- Almost every mile is commuting and the business barely leaves the house
- You're early and the bigger job is revenue, not optimizing the car
Make money. Then clean up the vehicle rules. Don't buy a deduction you can't support.
The short version
- Vehicle deductions are about business use, not vibes or vinyl wraps.
- Choose standard mileage or actual expenses on purpose.
- A real mileage log beats a March reconstruction.
- Commuting and personal miles don't count.
- Honest percentages survive. Inflated ones don't.
- Tie the car to clean books and a planning conversation, not a once-a-year guess.
FAQs
Can I deduct my car if I have an LLC or S-corp?
Entity type doesn't invent a deduction. You still need business use, a method, and records. How the car is owned (personal vs company) changes the paperwork and reimbursement path. Ask before you title the next vehicle.
What is the standard mileage rate?
The IRS sets a cents-per-mile rate (and sometimes different rates for certain uses) each year. Use the rate for the year you're filing. Confirm the current figure on IRS.gov before you calculate.
Is commuting tax deductible?
Generally no. Driving between home and your regular workplace is personal. Business miles are for business purposes beyond that commute pattern.
Should I use standard mileage or actual expenses?
Run both with real numbers once, then choose with your advisor. Simple miles often win for lighter use. Actual can win when costs and business use are both high. First-year choices matter.
Do I need a mileage app?
You need contemporaneous records. An app helps because you'll actually use it. Paper or phone notes work if you're consistent.
Can I write off a new truck in year one?
Sometimes large deductions exist under depreciation and expensing rules when the vehicle and business use qualify. This is fact-specific and easy to get wrong. Don't buy based on a social media clip. Model it first.
References
- IRS — Publication 463, Travel, Gift, and Car Expenses
- IRS — Standard Mileage Rates
- IRS — Topic 510, Business Use of Car
- IRS — Publication 946, How To Depreciate Property
- IRS — Recordkeeping
What to do next
Business owner guessing at miles, or sitting on a vehicle purchase with no method and no log?
At CEOHAVEN, we help entrepreneurs and real estate investors with tax planning, tax preparation, and bookkeeping. You should know what the car actually costs you after tax, with records that hold up.
Book a call. We'll look at how you use the vehicle, which method fits, and how to track it so the deduction is real.
It's not about how much you make. It's about how much you keep.