What's Your Fair Share?
Enter both incomes and your shared bills to see what each of you should fairly contribute — not just an even split down the middle.
About the book behind this calculator
Newlywed Money Management tackles income differences directly: when partners earn different amounts, an even 50/50 split of shared bills can quietly strain the lower-earning partner more than the higher earner, even though the dollar amount is identical. The book's fix is proportionate contribution — each partner puts in the same percentage of their income toward shared expenses, so the split scales with what each of you actually brings home.
The book is also clear that financial contribution isn't the whole partnership: household management, emotional support, and caregiving all count too, even when they don't show up on a bank statement. The math below is just one part of a fair partnership, not the whole of it.
Enter both incomes and your shared expenses to see your own proportionate split.
View Newlywed Money Management on AmazonWant this breakdown emailed to you both, plus a nudge for your next money date from Newlywed Money Management?
Thanks — check your inbox!
Enjoyed this? Explore the whole White Pine Finance series →
How these numbers work
How fair-share contributions are calculated
We add both partners' take-home incomes together, then find what percentage each partner contributes to that combined total. Each partner's fair share of your shared expenses uses that same percentage — so if Partner A earns 60% of your combined income, Partner A's fair share is 60% of your shared bills, and Partner B covers the remaining 40%.
Why not just split everything in half?
An even 50/50 split can quietly cost the lower-earning partner a much bigger share of their own paycheck. Splitting proportionally to income means each partner keeps roughly the same percentage of their own take-home pay free for everything else — savings, personal spending, whatever matters to them.
What this calculator doesn't do
- It doesn't categorize your spending — no needs/wants/savings breakdown, just the shared bills you enter here.
- It doesn't tell you how to structure your accounts — joint, separate, or a mix of both work with this math.
- This is a starting point for a conversation, not financial advice — see Chapter 2 of Newlywed Money Management for the full discussion of proportionate contribution.