I have purchased extra points a couple of times to make up for a shortage. For our October flight I purchased 2000 points for $50 for one leg of my husband's flight. The one way cost was $144 but I paid $50 for the points and purchased the one way flight with the total points. So I paid $50 instead of $144. The remaining points stay in the RR account. Not a huge savings and others may prefer to save up the points but I was comfortable paying the $50 for the points needed.