Tire size affect speedo?

I’ve been reading through a bunch of posts about changing the tire size on our cars to wider tires but keeping the same aspect ratio ( like from 215/60 R15s to 255/60 R15s). Has anyone seen a change in their speedometer reading due to these types of tire changes? Seems like if the new tire results in a larger diameter the speedometer would show a slower speed than actual. If so, what do you do to solve this?
Author: Mikes72