How to split rent fairly with roommates

Splitting rent equally is simple, and it is fair when the rooms are alike. When one room is twice the size of another, or has its own bathroom, an equal split quietly asks someone to pay for space they do not have. That is how resentment starts in a shared apartment.

This guide covers four ways to split rent, when each one is fair, and how to keep the monthly bills straight once you have agreed. Methods 1 to 3 use the same apartment: three roommates and a rent of $3,600 a month.

Agree on the method before you move in

The fairest method is the one everyone agrees to before the first rent is due. Once people have picked rooms, every conversation about money becomes a conversation about who got the better deal.

Sit down together and settle three things:

• How the rent is divided, using one of the methods below.
• Which bills are shared, and how: internet, electricity, water, gas, cleaning, groceries.
• Who pays the landlord, and when everyone else pays that person back.

Write the answers down somewhere everyone can see them. A shared note is enough.

Method 1: Split it equally

Divide the rent by the number of people. Three roommates and $3,600 means $1,200 each.

When it is fair: the rooms are about the same size, and nobody has a private bathroom, a balcony or noticeably more light. It is also the right choice when you would rather keep things simple than squeeze out the last few dollars.

Method 2: Split by room size

Measure each bedroom and split the rent in proportion to its floor area. The bigger your room, the bigger your share.

Say the three bedrooms are 180, 140 and 120 square feet, 440 in total:

Room	Size	Share of rent
Room A	180 sq ft	$1,473
Room B	140 sq ft	$1,145
Room C	120 sq ft	$982
Total	440 sq ft	$3,600

Each share is the rent multiplied by that room’s size, divided by the total: $3,600 × 180 ÷ 440 = $1,473. Amounts in these tables are rounded to the dollar.

This method has a flaw: it treats the whole rent as paying for bedrooms. But everyone uses the kitchen, the living room and the hallway equally. So many apartments use a mix.

A fairer mix: shared space equally, bedrooms by size

Split the rent into two parts. One part pays for the space everyone shares and is divided equally. The other pays for the bedrooms and is divided by size. Half and half is a common choice.

With the same apartment, $1,800 is split equally ($600 each) and $1,800 by room size:

Room	Equal part	By size	Total
Room A	$600	$736	$1,336
Room B	$600	$573	$1,173
Room C	$600	$491	$1,091
Total	$1,800	$1,800	$3,600

The difference between the biggest and smallest room is now about $245 a month instead of $491, which most people find easier to accept.

Method 3: Adjust for features

Sometimes size is not the issue. One room has an attached bathroom, a balcony or air conditioning, and the others do not. Agree on what that is worth each month, add it to that person’s share, and split the rest equally.

If the room with its own bathroom is worth $240 more, that roommate pays $240 plus a third of the remaining $3,360:

• Room with the bathroom: $240 + $1,120 = $1,360
• The other two rooms: $1,120 each

The total is still $3,600. The amount is a judgement call, so agree on it before anyone picks a room.

Method 4: Split by income

Couples and close friends sometimes split by what each person earns rather than by space. If one partner earns 60% of the household income and the other 40%, a $2,400 rent becomes $1,440 and $960.

When it is fair: people who share finances or plan to, and who are comfortable talking about pay. Among roommates who are not partners it usually feels intrusive, so a space-based method is the safer default.

What about the bills?

Most roommates split recurring bills equally, even when the rent is split by room. Everyone uses the internet, the water and the kitchen.

A typical month might be $120 for electricity, $450 for groceries and $60 for the internet: $630 in total, $210 each.

Two exceptions are worth agreeing on up front:

• Electricity with air conditioning. If one person runs the air conditioning all night and the others do not, an equal split can be unfair. Some roommates agree on a fixed monthly top-up for that room.
• Guests who stay often. A partner who is there most nights uses water, power and groceries. Agree whether that counts.

Deposits and one-off costs

The security deposit is usually paid by one or two people at the start. Record it as money owed to them, split the same way as the rent, so nobody forgets who put in what. The same goes for furniture and appliances bought for the apartment: agree whether they are shared, and who keeps them if someone moves out.

Keeping track every month

The method is the easy part. What causes arguments is the running tally: who paid the landlord this month, who bought groceries, who still owes for the electricity bill from March.

A few habits keep it clean:

1. One person pays the landlord, and everyone else pays that person back.
2. Record every shared expense when it happens, with who paid and who it is split between.
3. Settle up once a month, so balances never grow large enough to be awkward.

How to do this in STLD

STLD is a free app for splitting expenses, and every method above is built in:

• Make a Home group for the apartment and add your roommates by name. They do not need the app to be in the group.
• Add the rent once and set it to repeat every month, so it appears on its own.
• Choose how it is split. Equally for method 1. By shares for method 2: shares of 9, 7 and 6 give exactly the same split as 180, 140 and 120 square feet. Unequally to enter the amounts from the mixed method. By adjustment for method 3, with $240 extra on the room with the bathroom. By percentages for method 4.
• Add bills as they come, by typing, scanning the receipt or saying it out loud.
• STLD shows each person’s balance in plain words. Turn on simplify debts in the group’s settings and it works out the fewest payments that clear everything.

If your apartment is already on Splitwise, you can import your groups and keep going. For a trip with the same friends, read how to split trip expenses with friends.