You won't be getting double when you order your next double-double at Tim Hortons, but you will be getting a little more. The coffee giant is boosting the sizes of all its cups, starting next Monday.

That means if what you really want is a small coffee, you'll need to order an extra small, because the current medium-sized coffee will now be called a small.

What is now a large coffee will be a medium, while the extra large coffee becomes the large size.

And taking over for the extra large is a new, giant 24-ounce cup. (At 710 millilitres, that works out to roughly 3 fluid cups. Best to plan your washroom pit stops before taking one of those on the road.)

The prices for each cup size will not change, just their names.

The new sizes are being phased in after the popular coffee chain tested the new sizes in a couple of markets over the fall and early winter.

"The response has been overwhelmingly positive," said Dave McKay, the director of brand marketing for beverages at Tim Hortons. "Our guests also told us that they love our small eight-ounce cup, so we will continue to offer that size (as the extra small)."

The cup size change also brings Tim Hortons sizes more in line with competitors, including Starbucks, Second Cup and McDonald's.