Splitting bills as a couple: equally or by income?

Couples can split shared bills in two ways: equally (50/50) or in proportion to income. If one person takes home €3,000 a month and the other €2,000, under the proportional model the first pays 60% of every shared bill and the other 40%.

Both are fair. Just in different ways. 50/50 is equal; 60/40 is equally burdensome. A simple calculation with your rent including heating and service charges shows which model suits you. We'll go through it once from start to finish here.

Key takeaways

• With take-home pay of €3,000 and €2,000, the ratio comes out at 60/40, because €3,000 out of a total of €5,000 is exactly 60%.
• Rent of €1,200 including heating costs each partner €600 with an equal split; at 60/40 it's €720 and €480.
• With 50/50 and €1,830 in fixed costs, the lower earner spends almost 46% of their take-home pay on them, the other just over 30%; at 60/40 it's around 36.6% for both.
• Private expenses such as a mobile phone contract, clothing or hobbies don't belong on the shared tab under either model.
• If an income changes, for example through going part-time, a job change or parental leave, you need to recalculate the percentage, otherwise the model no longer adds up.

What does splitting bills as a couple mean?

Splitting bills as a couple means deciding which costs belong to both of you, what formula you use to divide them and when you settle the difference. That's three decisions. If one of them is missing, the arguments start within three months at the latest.

In practice, each person rarely pays exactly their share. The rent goes out of the main tenant's account, the weekly shop is sometimes paid by him, sometimes by her, and electricity and internet are tied to one of the two accounts. At the end there's a balance: who has paid out more than their share, and how much does the other person owe?

The splitting formula decides what that balance looks like. With 50/50 you can work it out in your head. With 60/40 you need a formula, which we show further down. The only thing that matters: the formula applies to all shared bills in the same way, not one way one time and another way the next, depending on mood.

How does 50/50 work, and when does it become unfair?

Under the 50/50 model, each person pays exactly half of every shared bill, regardless of income. If the shopping costs €84, each pays €42. The model is simple, transparent and doesn't require anyone to disclose their salary.

That's exactly why many couples start with it. It feels like an equal footing. Nobody is financing the other. And as long as both earn similar amounts, that's perfectly fine.

It becomes unfair when the incomes are far apart. Then both pay the same euro amount, but not the same share of their money. Typical warning signs:

• One person turns down meals out or holidays because there's hardly any leeway left after rent and fixed costs.
• The higher earner picks the bigger flat, but both pay half of it.
• At the end of the month, one person saves several hundred euros and the other saves nothing.

The problem is rarely the bill itself. It's the feeling that the shared standard of living is being subsidised by the person with the smaller budget, even though they can't really afford it.

How do you work out your share by income?

Your share by income is calculated with one formula: your own take-home pay divided by your combined take-home pay. With €3,000 and €2,000, that's 3,000 / 5,000 = 0.6, i.e. 60%, and for the other person 2,000 / 5,000 = 0.4, i.e. 40%.

Here's how to go about it:

1. Settle on take-home pay. Use what actually lands in your account each month. Gross pay distorts the picture, because tax class and deductions can differ.
2. Include irregular income or consciously leave it out. Christmas bonuses, performance bonuses or side jobs: either you divide your annual net income by twelve, or you leave one-off payments out. The main thing is that you both do it the same way.
3. Calculate the percentage. Your own take-home pay divided by the sum of both, times 100.
4. Round. 61.3% to 38.7% is precise but impractical. Many couples round to neat figures like 60/40 or 65/35.
5. Set a review date. Recalculate once a year or whenever a salary changes.

If you don't want to do it by hand: our article on the calculator for fair household costs works through a 64/36 ratio, including questions about rounding.

Example: rent and fixed costs at 60/40 instead of 50/50

With rent of €1,200 including heating, both pay €600 each under the 50/50 model. Under the 60/40 model, the person taking home €3,000 pays €720 and the one taking home €2,000 pays €480. The difference is €120 per person per month, or €1,440 a year.

It gets more interesting when you look not just at the rent but at all shared fixed costs. Our example couple has these monthly costs:

• Rent including heating: €1,200
• Electricity: €90
• Internet: €40
• Groceries and toiletries: €500

That's €1,830 a month in total. Here's how the burden is distributed:

	50/50	60/40
Person A (€3,000 take-home) pays	€915	€1,098
Person B (€2,000 take-home) pays	€915	€732
A keeps	€2,085	€1,902
B keeps	€1,085	€1,268
Share of A's take-home pay	30.5%	36.6%
Share of B's take-home pay	45.75%	36.6%

The last row is the heart of it. With 50/50, Person B spends almost half of their take-home pay on the shared household, Person A not even a third. With 60/40 the burden is identical: both spend 36.6% of their income on their life together.

There's a third variant some couples use: equal leftover budget. Here each person pays enough that both are left with the same amount afterwards. With €5,000 combined take-home pay minus €1,830 in fixed costs, €3,170 remains, so €1,585 each. Person A would then have to contribute €1,415, Person B only €415. It's consistent, but a big step. It suits couples who already live as one economic unit, for example with children or a joint pot.

Which bills do you share, and which stay private?

Shared bills are all those both of you benefit from equally: rent including heating, electricity, internet, contents insurance, groceries, cleaning products and streaming subscriptions you both use. What only one person uses or ordered stays private.

Shared	Private	Grey area, agree beforehand
Rent incl. service charges	Mobile phone contract	Car
Electricity, internet	Clothing, cosmetics	Holidays
Groceries, toiletries	Hobbies, gym	Pet
Contents insurance	Personal loans	Meals out
Broadcasting licence fee (only charged once per household)	Gifts for each other	Furniture

The grey area is where arguments start. Maybe the car is mainly used by one person to get to work, and both use it at weekends. Simple rules help here: fixed costs like insurance in proportion, fuel by usage. With furniture, it's worth asking who gets the sofa if you split up. Whoever keeps it pays for it, or you note down each share.

Meals out are a special case. Many couples split fixed costs by income but go 50/50 when eating out, because it feels more spontaneous. Others take turns paying. If you're out with friends and everyone orders something different, splitting by item is usually more relaxed than a flat amount per head.

Which model suits whom, and when does neither fit?

50/50 works if your take-home pay differs by less than roughly a fifth and you both want a similar lifestyle. Splitting by income works if the gap is bigger or one person largely sets the standard (size of the flat, location).

50/50 makes sense if:

• you both earn similar amounts,
• you've just moved in together and financial independence matters to you,
• you don't want to disclose your salaries.

Proportional makes sense if:

• your incomes are far apart,
• one person has noticeably less leeway,
• you want a bigger flat than the lower earner could afford on their own.

Neither model fits if:

• one person temporarily has no income at all, for example while studying or on parental leave,
• you run everything through a joint account and no longer keep separate accounts anyway,
• one person is paying off large debts that eat heavily into their available take-home pay.

In these cases, an agreed fixed amount works better, or you calculate using income after the loan repayment. To be honest: no model is automatically fair. What's fair is whatever you both consciously agree on.

How do you choose your model and stick to it?

A splitting model holds up when three things are settled: the percentage, the list of shared expenses and a fixed settlement date, such as the first of each month. Without a fixed date, open amounts pile up and grow into a sum nobody likes talking about.

Here's how to do it in practice:

1. Sit down once. Thirty minutes, both bank statements, a list of all recurring costs.
2. Decide on the model. 50/50, proportional or a mix. Write it down.
3. Sort out the grey area. Car, holidays, pet: one rule each.
4. Record everything in one place. Not in your heads, not in three different chats.
5. Settle up in one go. One transfer a month instead of twenty small amounts.
6. Review once a year. Salaries change, and so does the ratio.

Many people underestimate point 5. Transferring money back and forth straight away for every coffee and every shop is wearing and creates the feeling that you're constantly keeping score. Better: note expenses as you go, at the end of the month there's a balance, and one person transfers one amount. Done.

If you don't want to type up receipts, you can take a photo of the receipt and record it straight away as an expense. That saves the most time on the weekly shop.

Frequently asked questions

What if one person currently has no income?

While studying, unemployed or on parental leave, an income formula gives 100/0, which is rarely what anyone wants. Couples then usually agree on a fixed monthly amount that the person without income contributes from savings, BAföG or Elterngeld (parental allowance). Decide when you'll go back to the old formula, otherwise the temporary arrangement stays in place forever.

Is a joint account better than settling up?

A joint account saves you the monthly settling up, because both pay in their share by standing order and all shared bills come out of it. The downside: spending outside the account, such as a spontaneous shop on a personal card, still has to be tracked. Many couples combine both: a standing order for fixed costs, a running balance for everything else.

How often should we settle the difference?

Once a month is enough for most couples, ideally right after payday. For large one-off purchases like a washing machine, settling up immediately can make sense so that the balance doesn't build up to several hundred euros on one side.

Do savings or assets count in a proportional split?

As a rule, no, because the formula is based on ongoing take-home pay. But if one person has, say, rental income or interest that comes in regularly, it's only fair to include it in the calculation. Better to leave one-off inheritances or reserves out of it, otherwise the discussion quickly becomes a matter of principle.

Your first settlement month: how to get started

Take your rent including heating and the three or four biggest shared fixed costs, work them out once at 50/50 and once at your income ratio, and look at the row showing what percentage of each person's take-home pay goes on them. That one number usually answers the question on its own.

After that, all you need is one place for your expenses to go. With Split The Bill you set up rent and electricity as recurring bills, snap a photo of the shopping receipt and can see the current balance at any time. The maths is deterministic, not an AI estimate. And if your partner doesn't want to install yet another app: they don't have to. Everything runs in the browser, no app download needed. No catches, no forced sign-up for the other person. Just get started and settle up once at the end of the month.