Most owners think of maintenance as a set of tasks: oil, filters, brake checks, fluid changes. The records that prove those tasks were done are a separate job, and it usually falls to the owner by default. Deciding who keeps those records, and how, is one of the quieter choices in owning a car with a service contract, because the answer shows up only when a claim needs support.
The three ways records get kept
You can keep them yourself, with paper invoices in a folder or a digital copy in a single place. You can rely on the shop that does the work, which may keep its own digital history and give you copies on request. Or you can split the job, with a shop handling larger services and you logging smaller work you do at home. Each option has a different weak point. Your own folder can be lost. A shop's history can be hard to get after it changes hands. A split system needs a clear rule about which items go where.
What counts as usable proof
A useful record usually shows the work performed, the parts used, the mileage at the time, and the name of the place that did the work. Receipts for parts you bought yourself can help, but they are weaker if they do not say what the parts were for. Check your own contract for what it asks you to keep and for how long, because requirements vary.
Questions to ask before you choose
Will the shop give you a copy of each invoice on the day of service, not only a summary later? Can you get the full history if you change shops? If you do some work yourself, what will you write down, and where will it be stored? Does your contract accept records from any qualified shop, or only from certain ones? Which of these answers would you need if a claim were questioned?
A simple habit that works
Whatever system you choose, keep the original paper or a clear scan, note the mileage each time, and store the file where a household member can also find it. Review it once in a while to make sure it is complete. A contract is only as useful as the records that support it, and this part of the paperwork is entirely in your hands.
For the terms that differ between companies, the vehicle service contract companies compared, term by term table lists how each one is set out in its published terms.