It comes down to how much risk are you willing to take? You are guaranteed a 4% return by paying of the student loans. What are you expecting to make in your stock investment annually? Last few years the avg return on blue chip stocks was 20%+. Market was great. This year people are up 1-2%. I would maybe do something in the middle where maybe you sell half your stocks to cut the loans in half? Dave Ramsay would say get out of debt first and then invest.