All's you have to do when presented a bill you going to pay with using cash, you hand them a $20 for a 8.06 purchase, is to tell them to give you the folding money and for them to keep the change. Then your not burdened with all that change in you pocket.  When you write a check for something, round it up to the next $ and tell them to keep the change. If something is auto paid, Tell them to round it up to the next $.   Your problems will be solved.