Free tool
Expense split calculator for unequal incomes
A calculator for couples who want to know who should contribute what to the shared budget. Enter your incomes and shared costs - you will see the fair share for each of you and how much more the lower earner pays under a 50/50 split.
Fair split
On real bills
| You | Partner | |
|---|---|---|
| Rent and housingPLN 2,200 | PLN 1,298 | PLN 902 |
| GroceriesPLN 1,200 | PLN 708 | PLN 492 |
| Utilities and subscriptionsPLN 600 | PLN 354 | PLN 246 |
The category split is an example - the sharing proportions are yours.
With a 50/50 split your partner pays PLN 360 more per month than their proportional share. That is PLN 4,320 a year.
In practice: you pay the rent, your partner pays the rest. At the end of the month you owe your partner PLN 160.
A calculator will not track that. OurMoney does it automatically after every expense.
Signing up takes 30 seconds. You can invite your partner in the second step.
Indicative calculation. The app also has a third mode - tracking only, without splitting expenses.
How to split expenses in a relationship with unequal incomes
The rule is simple: each of you covers the same percentage of shared expenses as your income represents in your joint income. With salaries of 6500 zl and 4500 zl the joint income is 11 000 zl, so the shares are 59% and 41%. With 4000 zl of shared expenses that means 2360 zl and 1640 zl instead of 2000 zl each.
A difference of 360 zl looks minor until you look at what is left after the bills. Under a 50/50 split the person earning 4500 zl keeps 2500 zl while their partner keeps 4500 zl - almost twice as much. Under a proportional split they keep 2860 zl and 4140 zl, so you both hand the same fraction of your money to the shared budget. That is the whole difference between "we pay the same" and "it feels the same".
Count as shared everything you both use: rent or the mortgage, utilities, food, transport, trips. Keep personal shopping, hobbies and gifts for each other outside the shared budget - otherwise the question of who pays what turns into auditing every coffee. The result is a starting point for a rule, not a verdict: you can round the amounts or agree on your own proportions.
Equally, proportionally, or your own proportions
These three rules map to the three splitting modes in OurMoney. The calculator covers the first two, the third one you set in the app.
Equal split (50/50)
Each of you pays half of the shared expenses, regardless of income.
For couples with similar incomes - the simplest to calculate and the easiest to keep track of.
Proportional to income
Your share of the shared costs matches your share of the couple’s joint income.
For couples with a clear income gap, when 50/50 leaves one person with no breathing room.
Custom proportions
You set the split yourself, for example 60/40, and keep it regardless of salary swings.
When income is irregular or you have a reason to depart from pure maths - parental leave, one partner’s loan, a shared goal.
Splitting expenses as a couple - common questions
Is a proportional split fairer than 50/50?
When incomes differ a lot, a 50/50 split hits the lower earner much harder - after the shared bills they have far less money left. A proportional split evens out that burden. There is no single right answer, what matters is choosing a rule deliberately and both agreeing to it.
How do we split expenses when one of us earns twice as much?
With incomes of 8000 zl and 4000 zl the shares are 67% and 33%. Out of 4500 zl of shared expenses that means 3015 zl and 1485 zl instead of 2250 zl each. The lower earner is left with 2515 zl instead of 1750 zl - 44% more free money, and that gap usually decides whether a shared budget survives without tension.
What counts as a shared expense?
Anything you both use: housing, utilities, food, household supplies, transport, joint trips and subscriptions. Personal spending - clothes, hobbies, seeing friends, gifts for each other - stays outside the shared pool. The narrower and clearer your definition of a shared expense, the fewer arguments over individual receipts.
How do we count income when it is irregular?
Use the average of the last three to six months. With large swings (freelance, commission, seasonality) it is easier to set the proportions once a quarter than to recalculate every month. Count net income - what actually lands in your account.
Do we need a joint account to split expenses?
No. A joint account makes paying bills easier, but it is not required. Plenty of couples keep separate accounts and settle the difference with one transfer a month - the calculator shows exactly who owes whom. In OurMoney you see the same settlement continuously, without a shared bank account.
How often should we recalculate the proportions?
With stable salaries once a year, or after a raise or a job change. With irregular income, once a quarter. Recalculating more often rarely changes the outcome enough to be worth it, and it costs the rule its most valuable feature: predictability.
Does OurMoney do this automatically?
Yes. You set the splitting rule once and every shared expense is divided automatically - proportionally to income, equally, or by your own custom proportions. You also see who has already paid how much and who settles up at the end of the month.
More on shared finances
On the blog we write about shared household budgets, money conversations in a relationship and savings goals for couples.
Read the blogSee how simple shared finances can be. Start building a fair relationship today.
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