Most people think the only reason to buy their own engine oil for their vehicle would be if they wanted to change the oil themselves to avoid paying someone else to do it. The truth is most garages and dealerships will allow you to bring your own oil if you simply ask. They will even charge you less for the oil change because they typically remove the cost of the bulk oil they would normally be putting in your car from the bill.
Changing your own oil can be a huge pain because you have to learn how to do it first of all, then buy the oil, filter, and other necessary stuff, then get dirty doing it, and finally find an environmentally responsible way of disposing of the oil. When a standard oil change can be as cheap as $30, it hardly sounds worth all that hassle to me!
However, simply buying your own oil and bringing it with you to the oil change is so dead easy that anyone could do it. But, the real question is: will it save you money?
If you are using standard engine oil and buying it at the regular price at Canadian Tire, then the answer is almost certainly no. If you are using synthetic oil on the other hand and getting it at a good price, then the savings can be huge.
For instance, I stock up on Mobil 1 fully synthetic oil in 5L jugs whenever I cross the border into the USA for a trip or for other reasons. It usually costs somewhere between $20 and $22 each. A similar 4.4L jug (not even 5L) of oil costs $50 at Canadian Tire. Insane! If you wait for a sale at Canadian Tire, it drops to about $35 a piece.
Now, just do the math. Most places in Canada will charge you at least $80 and often $100 or more for an oil change using bulk synthetic oil that is of a lesser quality and name brand than Mobil 1. If you bring your own oil then they will charge you whatever the cost of a regular oil change is less approximately $10 for the oil they aren't using.
I go to a local garage and they charge me $15 I think for an oil change if I bring my own oil, including taxes, giving me a total cost of around $38. If you go to a dealership or higher end garage then you're probably looking at $25 to $30 plus the cost of your oil. Being conservative, I would have paid $80+tax = $90.40 somewhere else for the same end result, possibly with cheaper oil in the engine. That's a savings of $51.40 per oil change which is entirely worth it don't you think?