Sometime around April, your tax preparer asks one simple question: did you keep a mileage log? You did plenty of driving last year (you know that much), but there's no log to hand over. Just a year of jobs scattered across a calendar, a pile of invoices, and a truck with a lot more miles on the odometer than it had last winter.
So you do what most owners do. You either guess a low, safe number so nobody asks questions, or you skip the deduction entirely because you can't back it up. Both of those cost you real money, and the second one is the more expensive mistake by far.
Here's the good news. Your calendar and your invoices already hold most of the proof you need: dates, addresses, and who you went to see. AI can help you turn that scattered record into a clean, dated mileage log. One hard rule before we start, though. The log has to match trips you actually drove, and we'll come back to that because it matters.
What those miles are actually worth
The IRS lets you deduct business driving at a standard rate per mile, and lately that's been right around 70 cents. It covers gas, wear, insurance, the whole cost of running the vehicle, rolled into one number.
Run the math on that and it wakes you up. Say you drove 8,000 business miles over the year, nothing crazy for a trade that's out on the road most days. At roughly 70 cents a mile, that's about $5,600 off your taxable income. Even a part-timer putting on 4,000 miles is looking at close to $2,800. That's not a rounding error. That's a real chunk of what you owe.
There's a second way to do it (the actual-expense method, where you track every gas and repair receipt), but most trades find the mileage rate simpler and about as good. Either way, it starts with knowing your miles.
Which miles count, and which don't
This is where owners trip up, so it's worth being plain. Not every mile on the truck is a business mile, and claiming the ones that aren't is how a clean deduction turns into a problem.
Trips that usually count:
- Job to job, driving from one customer's site to the next.
- Shop or home to a supply house, picking up parts and materials.
- Runs to the bank, the permit office, or a customer meeting for the business.
- A trip back to a site to fix or finish something.
Miles that usually don't count:
- Your commute. Driving from home to your regular shop and back is personal, not business, in most cases.
- Personal errands, even if you took the work truck.
One wrinkle worth a quick word with your preparer: if your home is your main place of business, the commute rule can work differently, and more of your driving may count. That's exactly the kind of thing to confirm, not assume.
Turn your calendar into a dated log
Now for the part AI is genuinely good at. If you can hand it a list of your jobs with dates and addresses, it can lay out a mileage log for you in a few minutes. Most of you already have that list sitting in a calendar, a scheduling app, or your invoices.
- Pull your job history into one place: export your calendar for the year, or copy your invoice list, anything with dates and addresses.
- Paste it into the AI and ask for a dated log with columns for date, where you started, where you went, the reason for the trip, and the miles.
- Give it your shop or home address as the usual starting point so it can fill in the "from" for each trip.
- Ask it to estimate the round-trip miles between each pair of addresses.
- Read every line and fix what's wrong before you save it.
That last step isn't optional, and the next section explains why.
The honest part: it has to be true
Reconstructing a log from real records is allowed, and it's a normal thing to do. Inventing trips you never took is not. One is paperwork, the other is tax fraud, and the line between them is whether the drive actually happened.
AI doesn't know that line. It will happily fill a gap with a plausible trip, round a distance up, or guess at a mileage figure that's off by a few miles. It also can't tell which of your drives were personal. That's your job, and only you can do it.
Treat the AI's draft as a first pass, not gospel. Check the distances against a maps app, since its mileage estimates can drift. Cut any trip that didn't happen or wasn't for work. Keep the calendar and invoices you built it from, because those are your evidence if anyone ever asks.
The five-second habit that beats all of this
Rebuilding a year at tax time works, but it's a pain, and it's always a little fuzzy. Capturing miles as you drive them is easier and far more solid. The trick is making it small enough that you'll actually do it.
Snap a photo of your odometer on January 1 (or the day you read this), so you've got a starting number. Then pick one tiny habit and stick to it. A quick voice memo when you get back in the truck, "Framingham to the Worcester supply house and back." A text to yourself. A mileage app that logs it by GPS if you'd rather not think about it at all.
Once a week, feed those notes to AI and let it update your running log. Five seconds a trip, a couple of minutes on Sunday, and next April there's nothing to reconstruct. If you'd like that weekly handoff set up so it runs on its own, that's the kind of thing we help Massachusetts owners with.
Worth doing this week
You don't need to solve the whole year today. A few small moves now put you way ahead of where you were.
- Photograph your odometer this week so you have a current reading on record.
- Export or copy last year's calendar and invoices into one document.
- Ask AI to build a dated mileage log from it, then read every line and cut anything that wasn't a real work trip.
- Pick one capture habit (voice memo, text, or an app) and use it on your very next job.
- Set a recurring Sunday reminder on your phone to update the log while the week's still fresh.
Do that and the mileage question stops being the dreaded one. You'll have the miles, the dates, and the deduction, and it'll be built on trips you really drove.