<prompt> Human: Hi PF!Im contemplating moving in with my SO in the next few months and, of course, the first thing that comes to my mind when I think about merging our two households is how to handle bills and finances. Ive read some great advice on here for married couples using Mint, keeping some savings separate but acquiring joint checking to pay out of for monthly expenses. One thing I did also see was a clear caution to non-married couples to NOT go in on joint checking in case the worst situation happens.Id like to open up the conversation a bit more and see what others think is the best approach for couples who arent quite to legal-married status, but want to budget and plan together more than typical roommates. What are the underlying differences, cautionary tales, and best practices in this type of situation? Also, if we transition to marriage, how will we have to pivot our behaviors that we set up as domestic partners?  <response>: Married couple finances are linked same savings andor checking accountsJust living together completely separate finances. However, its important to go over your financial situations so you know youre working together. Understanding savingspending habits of your partner is critical towards building a successful relationship. One thing I did also see was a clear caution to non-married couples to NOT go in on joint checking in case the worst situation happens.Yes. Same with housing, dont buy a house together unless youre married. Same with an apartment. Dont sign a lease together that you cant afford on your own. What are the underlying differences, cautionary tales, and best practices in this type of situation? Just make sure youre open and honest about incomes, savings, goals, retirement, investing, etc. If you have different ideas of what it means to save or whether or not you want to own a home, or retire early, then that can cause some issues that need to be resolved. A strict saver and a strict spender who live together may have some problems down the line. Spend one day a week for a while and go over how much you both spend, where you spent it, and how much youve saved, and where that money is going once saved 401k, IRA, savings account, student loans, CC debts, etc.. Its important to know each others financial situations such as income and expenses as well as spending and savings habits so the best way to figure that out is to talk to each other and lay out your finances. Perhaps you could both make Mint accounts or Personal Capital accounts and then compare and contrast with one another. Also, if we transition to marriage, how will we have to pivot our behaviors that we set up as domestic partners? Thatll depend on whenwhere you cross that bridge. Merging accounts isnt all that difficult and most banks are super friendly on helping out with that. But again, this is a step to take post-nuptials. For the most part though, assuming youve been living together for a while and your finances are sorted out then the after marriage step is easy. 