How do we combine our checking and bills after moving in together?

There is no single right structure, but the common models are fully joint, fully separate, or a hybrid. The hybrid, often called yours-mine-and-ours, works well for many couples: each partner keeps a personal account for individual spending, and you fund a shared account for joint bills, groceries, rent, and savings. Decide how to fund the joint account, either splitting fixed dollars or contributing proportionally to income so it stays fair when earnings differ. Set up automatic transfers on payday so the shared account is always funded. Agree on a spending threshold above which you check with each other before buying. Start simple and adjust after a few months once you see how the flow actually works. The key is transparency and a shared view of the big picture, not any particular account layout.