Splitting Expenses as a Couple With Different Salaries: 35% and 65%

To split expenses as a couple with different salaries, each person pays the same percentage that their take-home pay represents of the two combined. With $1,400 and $2,600 a month, that is 35% and 65%, or $630 and $1,170 out of $1,800 in shared expenses, versus $900 each with a 50/50 split.

The proportional method is a way of dividing costs in which each partner's share of the shared expenses matches their weight in the total net income. It is pure arithmetic, with no AI estimates, and takes about 10 minutes.

Key takeaways

• Start from the two net amounts that actually land in your accounts each month and divide each by their sum: the result is your percentage, and it stays valid until one salary changes.
• Apply the percentage only to truly shared items (rent, utilities, groceries, internet). Gym, phone and hobbies stay with whoever uses them, otherwise the share swells without anyone noticing.
• Before you accept 50/50, work out what each of you has left at the end of the month: if one is left with 36% of their net pay and the other with 65%, the split is not fair. With the proportional method, both keep 55%.

How do you split expenses as a couple with different salaries in 10 minutes?

You need three numbers: the two monthly net salaries, the total of the shared expenses and a calculator. You don't need a spreadsheet, a shared note on your phone is enough.

50/50 is a convention, not a rule. For married couples, the law where you live may already set a contribution in line with each partner's means, so check the rule that applies to you. For unmarried partners living together, the agreement between the two of you decides.

When your net pay is close, the difference between equal shares and an income-based share is a few dollars and 50/50 remains the simplest choice. The calculation below is for when one net salary is much higher than the other, as in our example: $1,400 versus $2,600.

Step 1: which salary do you write down, net or gross?

The net: the amount that reaches your account each month after taxes and contributions, because it is the only one each of you can actually spend. Take last month's deposit or your pay stub and write the two numbers side by side.

A few practical cases, so you write down an honest number:

• Extra monthly payments and year-end bonuses: pick one approach and use it for both of you. Annual net divided by 12 works, as long as it applies to both.
• Self-employment income, commissions, performance bonuses: use the monthly average of net income over several months (12 is a sensible choice), not the best month or the worst.
• Pay with fixed deductions: if a reimbursement or a loan is withheld from your pay, write down the amount that actually arrives.

Step 2: how do you turn the two net figures into percentages?

You divide each net figure by the sum of the two: share A = net A / (net A + net B). With $1,400 and $2,600 the sum is $4,000, so A weighs 1,400 / 4,000 = 0.35 (35%) and B weighs 2,600 / 4,000 = 0.65 (65%).

Round to the whole percentage point and check that the two shares add up to 100. If you round badly, the cents get lost along the way and at the end of the year someone has paid more without knowing it.

Step 3: how do you apply the percentage to each shared expense?

You multiply the amount of each item by each person's percentage, one item at a time, and add up the shares. Doing it item by item, rather than on the total, lets you see right away what each expense costs each of you and discuss just one when it changes.

1. List the shared items with their monthly amount. A bimonthly bill should be divided by two.
2. Multiply each amount by 0.35 (A) and by 0.65 (B).
3. Calculate the share of the partner with the lower percentage and get the other by subtraction: the sum always comes back to the total.
4. Add up the shares and check that they match the total expenses.

How much does it change in dollars between 50/50 and proportional on $1,800?

The partner with $1,400 net saves $270 every month, or $3,240 in a year. The other partner pays $270 more. The couple in the example has five shared items:

Item	Total	50/50 each	A (35%)	B (65%)
Rent	$900	$450	$315	$585
Utilities	$180	$90	$63	$117
Groceries	$500	$250	$175	$325
Internet	$30	$15	$10.50	$19.50
Shared leisure	$190	$95	$66.50	$123.50
Total	$1,800	$900	$630	$1,170

The real test is what is left in your pocket. With 50/50, A keeps $500 (36% of their net pay) and B keeps $1,700 (65% of theirs). With the proportional method, A keeps $770 and B $1,430: 55% of salary for both.

If even this seems too little for the lower earner, there is the equal-remainder method: you subtract the shared budget from the sum of the net amounts ($4,000 minus $1,800 is $2,200) and leave the same amount to each, $1,100. A would contribute $300 and B $1,500. It is a legitimate choice, more generous to the lower earner, but you need to decide it together.

What mistakes throw off the numbers?

Some mistakes shift the result without anyone noticing: using gross pay, counting occasional bonuses as fixed salary, dumping in expenses that belong to only one of you and not agreeing on what counts as shared.

• Gross instead of net. Tax rates rise with income, so the ratio between the two gross figures is not the ratio between the two net figures, and the higher earner looks heavier than they are.
• A bonus or overtime in the calculation. A one-off bonus is not a monthly figure. If one comes along, decide separately how to use it, for example as a shared fund, and leave the percentage as it was.
• Personal expenses in the pot. Subscriptions, phone, clothes, classes: if you put them among the shared costs, whoever has the higher share ends up paying part of the other's personal expenses.
• No agreement on what is shared. Write the list of items once. Is the Sunday coffee at the café shared? Decide now, not in front of the receipt.

How do you keep track of who paid what and settle up at the end of the month?

During the month, whoever has the card in hand fronts the expenses, so at the end of the month you compare what each of you paid with the share that is due, and whoever is in debt settles the difference with a single transfer. All you need is one column for what each of you paid and one for the shares.

An example with the numbers above. B fronted rent and utilities ($1,080), A groceries, internet and leisure ($720). A owed $630 and paid $720, so A has a $90 credit. B owed $1,170 and paid $1,080, so B owes $90. One $90 transfer and the month is closed.

If you prefer not to reimburse each other every month, you can pay your share with one transfer a month into a joint account and use it only for the shared items.

Frequently asked questions

How often should the percentage be recalculated?

When one of the two net amounts changes in a lasting way: a raise, a new contract, a switch to part-time. If A goes from $1,400 to $1,600, the sum becomes $4,200 and the shares are 38% and 62%. Set a review date anyway, for example once a year, even if nothing has happened.

What do you do if one of you has no income for a few months?

With a net income of zero the formula gives 0%, which is not sustainable for either of you. Agree on a temporary minimum share, or a fixed amount for the period, and a date to redo the calculation. Write it all down, so nobody feels it as a debt.

What if the home is in only one of your names?

Rent is split like any other item, but a mortgage payment on a home owned by only one of you is not a simple cost, because it builds equity that stays with the owner. You can split utilities and groceries in proportion and treat the mortgage payment separately. For large amounts, it is a good idea to talk to a professional before putting the agreement in writing.

Where do I start today?

Write the two percentages in a note that you can both see. Then apply them to the first three items: rent, utilities and groceries.

Split The Bill keeps the record of your shared money, that is, who fronted what and the end-of-month balance, with deterministic calculations and without your partner having to download an app: they just open the link in the browser.