How to keep a car maintenance log

By the Wrenchy team · Published October 19, 2026 · Updated October 20, 2026

What's the best way to keep track of car maintenance?

Write down every service when it's done: the date, the odometer reading, what was done, the parts and fluids used, who did it and what it cost, and keep the receipt. Paper, a spreadsheet and an app all work; what matters is that the log is complete and that something reminds you when the next service is due.

What to record for every service

• Date and odometer reading. Most intervals run on both.
• What was done. "Oil and filter change", not just "service".
• Parts and fluids, with brand, spec and part number: oil weight and spec (for example 0W-20, API SP), filter part number, coolant type. This is what proves the right parts went in.
• Who did it: you, or the shop's name and address.
• Cost, split into parts and labour if you have it.
• The receipt, or a photo of it. Thermal receipts fade, so photograph them.
• Notes for next time: what the mechanic flagged, tire tread depth, anything that's starting to wear.

If you do your own maintenance

You can service the car yourself without voiding the warranty: the FTC says you don't have to use the dealer for repairs or maintenance to keep it in effect. It also tells owners to keep records and receipts of oil changes, tire rotations, belt replacements, brake pads and inspections, whoever does the work^[1]. For DIY work that means:

• Keep the parts receipt and write the date and mileage on it, or log them the same day.
• Take a photo of the new oil and filter boxes next to the odometer. It's a timestamped record of what went in.
• Use the oil and parts spec in your owner's manual, and record it.

When you sell the car

Put the log and the receipts in one folder, in date order, and bring them to the viewing. Buyers look for the regular services at the right mileage and for receipts for the expensive jobs: timing belt, transmission, brakes and tires. If your log is in an app, export it so you can hand it over. More detail, with sources: which service records to show when you sell.

Paper, spreadsheet or app?

We make Wrenchy, an iPhone app that does most of the app column: reminders by date or mileage, notes on each record, and a CSV export of the whole log. It doesn't attach receipt photos to services, so keep the receipts (or photos of them) as well. Its records stay on your phone with no account, so it relies on your phone's iCloud or computer backup. Other apps compared.

Download on the App Store

Questions

Do I need receipts if I do my own oil changes?

Yes, keep them. The FTC says you can maintain the car yourself without losing the warranty, and also tells owners to keep records and receipts of oil changes, tire rotations, brake pads and inspections to show the car was maintained. For your own work, the receipt for the oil and filter, with the date and mileage written in your log, is that proof.

Is a paper logbook good enough?

It works if you keep it up. Its weak points are that it doesn't remind you when something is due, and it's gone if the car or the glovebox is. A photo of each page now and then fixes the second problem.

What do buyers want to see when I sell?

A record of when the regular services were done and at what mileage, and receipts for the big jobs (timing belt, transmission, brakes, tires). A buyer can't check work that was never written down, so a complete log is easier to trust than a verbal "it's been well looked after".

Does CARFAX already keep my history?

Only if the shop that did the work reports to CARFAX. Many dealers and chains do; plenty of independent shops don't, and nothing you do yourself is ever reported. So unless every service happens at a reporting shop, your CARFAX history has gaps you have to fill in by hand. Ask your shop whether it reports to CARFAX. See Wrenchy vs CARFAX Car Care.

Sources

1. FTC, Auto Warranties and Auto Service Contracts, April 2024

Typical service intervals, with their sources: car maintenance schedule.