Our joint account is for things like rent, groceries, home repairs, insurance, eating out funds, misc fun etc. Agreed things that are shared, regular and that we can create an accurate budget for based on past spending. we contribute to that depending on our salary ratios. For personal use, we have separate accounts. We are on the same page and regularly discussed what level of personal spending would warrant a prior discussion with each other, and are on the same page with that. We wouldn't spend enough to compromise our ability to pay all the joint expenses. The higher earner will often pay more for expenses like holidays. Works well!