Should you pay off credit card debt before you invest in an RRSP? Bruce Campbell of the BMO Financial Group advice -yes!

Because interest on your credit card can be as high as 22 per cent.  Once you've created the habit of putting money aside to pay down debt - make those monthly payments the basis of your RRSP contribution once the debt is eliminated. It just makes sense.
BMO also has a handy RRSP calculator you can link to here.