Budgeting as a couple: who pays for what?

Three methods, no single right answer

Fifty-fifty splits each shared cost into two equal parts. Proportional sharing has each person pay a share in proportion to what they earn. A joint account pools both contributions, whatever the calculation rule, and pays the costs from a single account.

None is better in itself. The one that lasts is the one both of you find fair, because you chose it together, with the figures in front of you.

A worked example

Alice earns €2,800 net a month, Hugo €1,700, making €4,500 between them. Their shared costs come to €2,200: rent €1,100, energy and internet €200, groceries €600, insurance €120, shared car €180.

Fifty-fifty, each pays €1,100. Alice is left with €1,700 and Hugo with €600: the gap widens, and Hugo’s budget is very tight.

In proportion to income, Alice pays 62.2% of the costs (2,800 ÷ 4,500), or €1,368.89, and Hugo 37.8%, or €831.11. Alice has €1,431.11 left and Hugo €868.89. Each puts the same share of their income towards shared costs, 48.9%, and so keeps the same proportion of what they earn.

Which costs are shared?

Before calculating, you need to agree on the scope. Generally shared: housing, energy, internet, groceries, household insurance, children’s expenses, the shared car and shared holidays. Generally personal: individual subscriptions, loans taken out alone, leisure, each person’s gifts.

Write the list down, with the amounts, and reread it once a year. Disagreements almost always come from a fuzzy scope rather than from the calculation.

The joint account: how it works

It works simply: each month, on payday, each person transfers their share of the shared costs to the joint account. The joint account pays the shared direct debits; whatever is left in each person’s own account is theirs to spend freely. Add a margin of 5 to 10% for shared surprises.

One legal point is worth checking with your bank: in principle, joint account holders are jointly liable for the account’s debts, overdraft included. That is a reason to put in only what is necessary.

When incomes change

Parental leave, unemployment, a pay rise: with proportional sharing, the split recalculates itself, as long as you actually do it. Go back over the figures whenever your situation changes and at least once a year. Some couples add an identical personal allowance for each, for example €150 each, so that both have the same freedom.

A third way: the same free money for each

Some couples prefer to equalise what is left rather than what is paid. You subtract the shared costs from total income, split the remainder in two, and each person contributes the difference. With Alice and Hugo: 4,500 − 2,200 = €2,300, or €1,150 free for each.

Alice then contributes 2,800 − 1,150 = €1,650 to shared costs, and Hugo 1,700 − 1,150 = €550, which does add up to €2,200. It is the most redistributive method: it suits couples who see themselves as a single economy, less so those who value their financial independence.

Talk about it regularly

Twenty minutes a month is enough: compare planned and actual, adjust an envelope, decide on joint savings. Also talk about each person’s debts, any major purchases on the horizon and shared goals, before they turn into tension. This article gives budgeting benchmarks and is no substitute for legal or financial advice.

• Which costs are shared, and which stay personal?
• Which method of sharing, and when will you review it?
• How much goes into joint savings, and for which projects?
• Who covers exceptional shared expenses up front, and how are they paid back?