From each according to their ability. If you make $50k and your spouse makes $150k, and your monthly expenses are $10k, then it seems quite reasonable for you

From each according to their ability. If you make $50k and your spouse makes $150k, and your monthly expenses are $10k, then it seems quite reasonable for you to put in $2500 and your spouse to contribute $7500. The nice thing about the joint spending account is that you can set up this arrangement and then subsequently ignore it for everything else. All communal bills just get paid, and you are free to spend your excess how you like. If either person takes issue with how the money is spent, then you break it down into what they're missing. If it's nothing, then what's the problem? And if there is something missing, then you can agree to increase what counts as communal bills, including vacations, retirement, etc. All the way to everyone contributing 100% of their income, which is just a traditional joint account (but I would strongly recommend against that; 80-90% should be the max).