RRSP contributions may come from payroll deductions or cash contributions which may lead to a tax rebate ; k s are funded with payroll deductions. A Group RRSP is set up by an employer for employees and is funded with payroll deductions, much like a k plan in the U. What Else Should I Know? IRA: What’s the Difference? Interested in taking the lead on your retirement savings strategy? It is administered by an investment manager and affords contributors the advantage of immediate tax savings. RPP: What’s the Difference?