As far as I know there is no set defined number of years. On the positive note it was one of Canon’s best sellers so that may influence them in providing spares. Covid and the declining sales of digital cameras has forced companies to cut back so there isn’t much incentive for them as they would make more money selling a new camera than from repair old ones.

Mint Chocs:

Yeah, I think as many people still use it, repairs and parts will still be available for some time. One small camera shop still has original 5d shutter replacement on their price list. Or maybe they just didn't update their web page for years, who knows.

I still want to know some average number of years after which official canon services stop to repair their discontinued cameras

Why don’t you contact the Canon official repair shop in your country and ask them.

Actually the practical thing to do is to ask them if they would service such and such, and for how much...
If the price is reasonable, sent the camera in for repair... :)

wbyoungphotos:

Yeah, true

Congratulations on the 5DIII! I believe you'll find repair service from Canon ends 5- to 10-years after the date the camera is discontinued, depending on the model line. They don't publish this information. You kind of discover it when you have an older body with a problem. I haven't had the slightest problem with either of my 5DIII bodies, both dating to 2013.