Ask HN: How do you and your spouse handle big income differences?

Personally, I would absolutely not want to try and be an accounting minutiae expert in my marriage. The point of making a good amount of money is not worrying about money. I make pretty close to triple what my wife makes right now, but that wasn't always the case and certainly isn't guaranteed to always be the case. The point of marriage is you're a single decision-making unit. It's a lifetime commitment. You weather the highs and lows and buffer for each other to make it easier and more pleasant than it would be if you were single. I had a really bad spine injury 8 years ago, and there was a period of nearly 6 months that I couldn't work at all. Without my wife, I couldn't have even put my shoes on, and I was earning zero for at least a short period of time due to being young and stupid and thinking independent contractor with no disability insurance was a fine thing. Well, guess what has happened since then? My wife has a condition that has put her in the ICU twice in the intervening years, and has had to switch jobs and go through a brief period of unemployment for the same reason. She didn't need to worry about money either during that time specifically because we're a single economic unit and bad things that happen to us individually don't need to happen to us together.

The way I treat making more money than her is both of us deposit paychecks into a single shared account. Most of what goes in there ends up in other accounts, either for retirement or mostly into brokerage accounts to invest what is over the limit for tax protected retirement accounts. Neither one of us really touches that, but it doesn't matter. Both names are authorized to withdraw if we wanted to. It's community property legally. At some point, one of us is going to die before the other. Given her medical profile, I'm likely to outlast her, but if I die first, am I gonna feel cheated that my wife gets a nice life because of all my work? Isn't that the point of work? To make things better for your family, not just for yourself?

Anything we buy or pay with the shared account is considered to be 50% hers and 50% mine, regardless of who actually puts more in the account. The logic behind this is that we both make the exact same "effort" in buying those things. So we pay for almost everything with that account: holidays, groceries, utilities, furnitures, ... . If we have extra, we put a bit in a savings account / investment and those also belong to us 50/50.

The benefit of this approach is the it protects both of us. If we decide to have children and that she should work part-time instead of full-time to raise them, she will still have the exact same 50% claim on everything. She will not loose more than I do. We'll just have less money coming in the joint account and will have to adapt our budget accordingly. This is thus a common decision that impacts the both of us equally.

Importantly, our mortgage/rent is also paid off the joint account, so the house belongs to each of us 50-50. I was however able to contribute to a bigger portion of the downpayment for the house. To make things fair, she agreed to sign an "acknowledgement of debt", recognising that she "owes me" half the difference between my contribution to the downpayment and hers. If we stay together, that letter is just a useless paper that sits on a notary desks and we'll never talk about it. If we split, the house will be sold, each of us will get 50% of the proceeds, but I will be able to claim that difference, making things fair.

The remaining 25% on each other private accounts can be used for private expenses. I never have to "justify" buying a video game or an impulsive luxury since it comes out of my private account, I can also go out with friends and not have someone that asks wether that $75 tab at the bar is justified or not. Anything we buy with the private accounts is considered to be 100% belonging to the person who bought it. This account is also used for surprise gifts (birthday, Christmas, ...) since the expenses do not appear in the shared account logs. We agreed that any inheritance will not be split and will remain in our private accounts, so there is no "cheating" there. Also, anything that we had "before" we setup this system remains in our private accounts.

If one of our private accounts becomes "big" and we start seeing some significant asymmetry between those (Eg: I inherent millions and she doesn't, so I could have an amazing life but the join account is frustratingly poor) we have the option of treating some part as regular "income" our of it (Eg: do an automatic payment of $xxx every month). Since this is an income, that amount goes 75% in the joint account and 25% remains in the private account. This increases the amount available on the joint account, so we can afford the cool things we wanted. But the bulk of the money stays in my private account so if we split she won't have any claim to any of it.

Of course, the 75% - 25% split is a decision we took, but you might wanna change percentages according to your situation. Overall we are extremely happy with this arrangement as it brings the financial discussions close to 0 (we had some before).

Works for things like shared housing situations too.

If you want to be even fairer, take $50,000 off the bottom, and then split all expenses for non-survival stuff proportionately to income over $50,000.