Two incomes, one home, 30 000 kr out the door every month

When you own together, it is no longer two budgets sitting side by side. It is one, with two incomes coming in and a long line of fixed expenses going out. The salary account often looks healthy on payday, and oddly empty the week before the next one.

In this post we set out a concrete monthly budget for a couple with a mortgage, shared building costs, and two ordinary incomes, plus a simple rule for splitting expenses without arguing about the maths.

What felleskostnader actually cover

Felleskostnader (the monthly fee homeowners in a Norwegian housing co-op or condominium pay for shared building expenses) are not a punitive tax for flat living. They cover things you would otherwise have to pay for out of your own pocket: a caretaker, snow clearing, maintenance of common areas, building insurance, often cable TV and internet, and in a borettslag (a Norwegian housing co-operative) also interest and instalments on the shared debt.

In a sameie (a Norwegian condominium where each owner holds title to their flat individually), municipal charges are usually billed directly by the kommune (the local municipality). In a borettslag they are typically rolled into the felleskostnader. Keep one thing in mind when comparing two flats: compare total housing costs, not just the mortgage payment.

A sample budget you can copy

The table below shows a couple where both work, own a flat worth 4.2 million NOK with 3.5 million in mortgage debt (25-year repayment, around 5.3 percent interest), and pay 5 500 kr in felleskostnader. The figures are a starting point, not a verdict. Swap them out for your own.

Item	Amount (kr/month)
Income after tax
Person A	38 000
Person B	32 000
Total income	70 000
Fixed housing costs
Mortgage (interest and repayment)	21 000
Felleskostnader	5 500
Electricity	1 800
Home contents and life insurance	700
Internet, mobile, streaming	1 500
Total fixed housing costs	30 500
Variable expenses
Food and groceries	10 000
Transport (public transport or car)	4 000
Clothes and personal	1 500
Leisure and eating out	4 000
Gifts and miscellaneous	1 500
Total variable	21 000
Saving and goals
Buffer (3 to 6 months of expenses)	5 000
Pension, ASK (a Norwegian share savings account) or equity funds	5 000
Holidays and big purchases	2 500
Maintenance and renovation fund	2 500
Total saving	15 000
Total spent	66 500
Left over for adjustment	3 500

The most important thing here is not the amounts, but the ratios. Housing costs alone claim 30 500 kr of 70 000, or 44 percent of income. That is fairly typical in Norway in 2025, and it explains why "spare cash" can feel like a rare visitor.

How to split expenses fairly

The simplest version is to split everything down the middle. That works fine when you earn roughly the same. When incomes differ, splitting expenses proportionally to income tends to feel fairer.

Here is how it works for the couple above:

• Person A earns 38 000 of 70 000, or 54 percent
• Person B earns 32 000 of 70 000, or 46 percent
• Joint housing costs are 30 500 kr. A pays 16 470, B pays 14 030
• What you have left for personal spending and saving is up to each of you

In practice, the smoothest setup is a joint current account that both of you transfer your share into on payday. The "who paid last time" debate disappears after a couple of standing orders.

For samboere (cohabiting partners under Norwegian law), this matters more than it does for married couples. Unlike spouses, you do not have a mutual duty to support each other, so it is wise to write down how you share the home and its costs in a samboeravtale (a cohabitation agreement).

Build a buffer and a maintenance fund from day one

When you own, there is no longer a landlord to pick up the bill when the washing machine dies. A small maintenance fund absorbs the shock. Two rules of thumb are enough:

• A buffer covering 3 to 6 months of fixed expenses, parked in a high-interest account
• A maintenance fund built up gradually, ideally 2 000 to 3 000 kr per month

In a borettslag, the shared debt covers a lot of the big building-related costs such as the roof and façade, but everything inside your front door is your own responsibility.

Where you have the most leverage to start

Most housing costs are slow to change. You can refinance the mortgage, but not every month. Felleskostnader are set by the board. What you can change at short notice is:

1. Check the interest rate you have. Ask your bank to match a better offer, or get quotes from two competitors, ideally once a year
2. Review your electricity contract, and choose fastrente (a fixed-price contract) or spotpris (a variable spot-price contract) based on your consumption
3. Tidy up your subscriptions. They pile up surprisingly fast in a shared household

These three steps take a couple of hours in total and can comfortably free up between 1 000 and 2 000 kr a month, often more.

A next step you can take tonight

Set aside an hour this coming Sunday, open the table above, and plug in your own numbers. Once you see total housing costs alongside total income, the rest of the maths suddenly gets much easier to talk about.

If you use Luma, you can import the transactions from your joint account and see where the actual numbers diverge from the plan. That is usually where the most valuable insight sits.