<prompt> Human: My SO and I have been together for a few years. He is financially responsible, but has no credit. I have poor credit, but have managed to get out of all credit card debt within the past couple of years and am now building my credit back up. We dont plan on getting married for many years, mainly for financial reasons he is still in school, getting financial aid, and I am paying off student loan debt. We usually split the cost of everything since neither of us make very much, but this can get confusing e.g., cant remember who bought the groceries last time. We are considering getting a joint credit card to build credit and simplify dealing with monthly expenses i.e., pay off the full balance each month and split the payment once. There is no doubt in my mind that this system would work for us. We have no trouble communicating about financial issues with one another and already have a system in mind for deciding when and when not to use the credit card for expenses. The reason that I am posting this is because I am unsure about the best way to go about selecting and applying for a card. I have read that for first time credit card applicants, it can be beneficial to build credit by becoming an authorized user on a card with good history. The problem is, my credit cards dont have great history nothing major, just a few late payments acquired in earlier years, before I fully understood the implications of this. If I add him as a user to a card that is now in good standing but has missed payments in the past will this negatively affect his credit? Alternatively, should one of us apply for a new card? Thanks in advance for any help!  <response>: Why not add your expenses in splitwise.com and settle the balance each month? I use this to keep track of expenses with multiple friends. 