Yes, when you buy it, ask the employee at the paint counter can tint it. For example, if you're painting a wall blue, they can tint the primer a light blue. It will make the paint cover better with fewer coats.Can primer paint (ie Kilz) be tinted? If so ,with what?
And if you're planning to make a big color change (painting a light color over a dark one, for example ... or if your new paint color is very dark or is red, which requires multiple coats), you really SHOULD have the primer tinted.
You can have it done at the store where you're buying the primer, right there at the paint counter. Walmart, for some reason, refused to tint the primer for me ... all other stores where I've bought paint (hardware, Home Depot, etc.) have done it willingly.
If you've already bought the primer and didn't have it tinted, either take it back or call the store to find out whether they'll tint it for you.