<prompt> Human: Greetings -- This is my first time here and I am not adept enough to add a flair, sorry!TL;DR: What would be a fair interest rate on a 6,00020-month personal loan from a family member?Actual story: 20 months ago, my now ex-husband cut me off from all marital funds. I borrowed 6,000 from a family member for my attorneys retainer. At the time, my attorney thought that we could get a settlement within six months and I told my family member that I would pay him back then.That didnt happen, so at the six-month mark I offered to start paying in installments or take out a personal loan to repay him, since I was then in a better position to do so. He declined and told me to pay when it was all settled. Of course, this doesnt matter as far as what I will pay, but Im just adding it to show that he was not hurting for the money.Its now been 20 months and settled! I will be going to my bank to get a cashiers check tomorrow. My family member did not mention interest but I would like to include it since he did not have use of this money for 20 months. What would be a fair amount? 300, 500, 600? If it matters, my family member is pretty conservative financially and it is highly unlikely that he would have been making high-growth, high-return, high-risk investments.And for the personal part of personal finance -- because of our respective financial positions and culturalfamily considerations, my family member would be offended if I were to give him what he saw as a gift of money. I want to be fair and Im perfectly willing to be generous, but I dont want to repay his kindness and helpfulness in a way that he would find offensive. I have been baking a lot of cookies and making freezer meals, though!  <response>: Communication is key.If I loaned 6k to a family member, Id be perfectly happy to get the 6k back with zero interest. I wouldnt really care if 6 months turned into 20. I might be a little upset if my family tried to pay me interest. To me, that would turn a favor into a business transaction.But if I loaned a family member 100k for several years, I might accept 3 interest.So I think its just a personal preference thing. You might say that you really appreciate the favor, and the flexibility since it took you a while to return the money, and that youd like to return the money with some interest, maybe 3. If they decline, be gracious, and just thank them again for helping you out. 