What do you have in writing as evidence of this loan and its terms? If you have nothing that will make it hard to collect, since there is no written agreement between the parties and the other party can state that his recollection of the repayment terms is different than yours, or even that it was a gift, and there will nothing in writing to refute that. I would put a letter to the person who owes the money stating in the letter that if you do not receive the payment by (set a date) that you are going to pursue legal action. In the interim, I would consult a local attorney to see what kind of case he or she thinks you have. NOTE: This is not legal advice, it is just educational information. Please consult a local attorney for legal advice. No attorney - client relationship is created by this post.