Most car owners know roughly when they last changed their oil. Fewer know the exact mileage, the oil weight used, or whether the filter was replaced too. A maintenance log fixes that. It turns vague memory into a searchable record — one that helps you make better decisions, catch problems earlier, and get more money when you sell.

1

Record the right details every time

A log entry with missing information is nearly as useless as no log at all.

  • Date of service — month, day, and year.
  • Odometer reading at the time of service.
  • Exactly what was done — "oil change" is good; "oil change, 5W-30 full synthetic, Wix filter WL10290" is better.
  • Parts used: brand, part number, quantity, and cost.
  • Labor cost if the work was done at a shop.
  • Notes on anything unusual — noises, conditions observed, what prompted the work.
2

Pick a method and stick to it

The best log format is the one you'll actually use consistently.

  • Dedicated app: Easiest for adding entries at the time of service; stores photos of receipts; sends reminders.
  • Spreadsheet: Good for detail and custom columns; requires a desktop to update comfortably; easy to export for buyers.
  • Paper notebook: Minimal friction; no app required; easy to lose or damage; hard to search.
  • Folder of receipts: Better than nothing; no structure; hard to summarize or query.
  • Whichever method you use, keep it with the car or accessible from your phone so you log entries immediately — not "later."
3

Set up your log before the next service

Starting a log feels daunting if you try to reconstruct years of history. Don't. Start clean.

  • Create one entry per vehicle today with the current odometer reading.
  • Add any services you remember from the last 12 months with approximate dates and mileage.
  • Log the next service completely, with every detail, from this point forward.
  • If you have old receipts, spend 20 minutes entering them. If not, just start fresh.
  • Don't let perfect history be the enemy of starting a good log now.
4

Handle receipts and documentation

Receipts are the proof behind your log entries. Treat them accordingly.

  • Photograph receipts immediately after service — paper receipts fade.
  • Attach the photo to the log entry so it's linked, not floating in your camera roll.
  • Keep physical receipts for major repairs in an envelope in the glovebox.
  • For warranty work, keep the shop invoice — you'll need it if a warranty claim comes up later.
  • Include the VIN on any major repair records so there's no ambiguity about which vehicle they belong to.
5

Log every service, not just the big ones

The gaps in a maintenance log are where problems hide.

  • Log cabin air filter replacements, wiper blade swaps, and light bulb changes — not just oil changes.
  • Record tire rotations and pressure checks with the actual PSI readings.
  • Note fluid top-ups between changes — unexpected consumption is a symptom worth tracking.
  • Log inspection results even when nothing needs doing — "checked brakes, 4mm remaining" is useful data.
  • Make logging a 2-minute habit at the end of every garage session, not an annual catch-up.
Resale tip: When selling, a printed or exported maintenance history from your log can be the difference between a buyer who trusts the car and one who haggles hard. Document your maintenance and let the record do the selling.

A maintenance log doesn't require much time per service. But over the life of a car, it becomes one of the most valuable documents you own. Start simple, stay consistent, and the log will take care of the rest.

For more on what to look for during your regular maintenance checks, see our 10 car reliability tips to prevent breakdowns.