The simplest fair way to split utilities and internet with roommates is to add up every shared bill for the month and divide it evenly, then settle once a month with as few transfers as possible. Split evenly unless there is a large, obvious difference in use, such as one person running a space heater all winter, and prorate by days when someone moves in or out partway through a month. Agree on all of this before the first bill arrives, and write it down where everyone can see it.
The rest of this post walks through a full example with three roommates, covers the cases where an even split stops being fair, and shows what the bills do to your own budget if your name is on the accounts.
Step 1: list every shared bill
Start with a short list of what the household pays for together. For most places that means:
- electricity
- gas or heating oil, if you have it
- water and sewer, if it isn't included in rent
- internet
- trash or recycling pickup, in some cities
Leave out anything only one person uses. A personal phone plan or one roommate's streaming account isn't a household bill, even if it's paid from the same card.
For each shared bill, note who holds the account, how often it's billed and roughly what it costs. Water is often billed every three months, so turn it into a monthly number to keep the math steady.
Step 2: work out each share
Say three roommates share a place. In a typical month the bills are:
- electricity: $120
- gas for heat and hot water: $54
- internet: $75
That's $249 a month. Water comes every three months at $90, which is $30 a month, so the monthly total is $279. Split three ways, each roommate's share is $93.
Some months will be higher. Heating bills can double in January and electricity can jump in August if there's air conditioning. That's fine: the split stays even, and the share follows the bill. If the swings make it hard for someone to plan, you can each pay a flat amount every month into the bills and settle the difference at the end of the year, but most households find it easier to split the real number each month.
Step 3: settle with as few payments as possible
There are two common ways to hold the accounts.
One person holds everything
One roommate has every bill in their name and pays them all. Each month the other two send that person their share. In the example, the account holder pays $279 and each roommate sends $93, so two transfers a month and nothing else.
This is the easiest setup to run. The cost is that one person carries the bills up front and is the one who has to ask when a payment is late.
Each person holds one bill
Spreading the accounts out shares the work, but it can turn into a lot of small payments if you settle bill by bill. Net it instead. Using the monthly numbers without water:
- Roommate A pays internet: $75
- Roommate B pays electricity: $120
- Roommate C pays gas: $54
The total is $249, so each share is $83. A paid $75, so A owes $8. B paid $120, so B is owed $37. C paid $54, so C owes $29. A sends B $8 and C sends B $29. B gets back exactly $37, and the month is settled in two payments.
Whatever you choose, pick one day a month to settle, such as the first weekend after the last bill posts. Paybacks that wait for "whenever" tend to get forgotten.
When an even split isn't fair
An even split works because the differences between roommates are usually small and hard to measure. Arguing over who runs the dishwasher more costs more goodwill than the few dollars it might change. A few cases are different.
Someone moves in or out mid-month
Prorate by days. Say a third roommate moves in on the 21st of a 30-day month, and that month's electricity bill is $120. The two original roommates were there all 30 days and the new one was there for 10. That's 70 person-days in total, so each person-day costs $120 ÷ 70, about $1.71.
- the new roommate pays 10 days: $17.14
- each original roommate pays 30 days: $51.43
The three amounts add up to $120.00. Do the same for each bill, or prorate the monthly total once if that's easier.
Internet is the usual exception. Many households charge a full month from the first full month someone lives there, since the speed and the price don't change with one more person.
One person uses a lot more
A space heater running all winter or a home office full of screens can move a bill. Measuring it precisely is rarely worth it. Agree on a fixed extra instead. For example, the roommate with the space heater pays an extra $15 a month from November to March, and everything else stays even.
Someone works from home
If one roommate works from home and needs faster internet than the others would pay for, a fair split is for everyone to share the cost of the basic plan and for that roommate to cover the upgrade. If the basic plan is $60 and the faster one is $90, the three of you split $60 at $20 each, and the person working from home also pays the $30 difference.
Rooms of very different sizes
Some households split rent by room size (our rent split calculator does that math). You can carry that into heating and cooling if the big room really does take more to heat, but most people keep utilities even and let rent carry the difference. It keeps the monthly math simple.
Write it down
A two-line note in the group chat is enough. Something like:
Bills are split three ways each month. The space heater in the back room adds $15 a month, November to March. We settle on the first Sunday of each month.
Put the names of the account holders in the note too, so nobody has to guess who to pay. If you use a splitting app, add each bill as it posts and settle from the app's balances, so the record and the payments match.
What the bills do to your budget
If you're the roommate whose name is on the accounts, your card statement shows the whole bill. In the first example that's $279 a month, but your share is $93. The $186 your roommates send back isn't income and isn't a refund from the utility company. It's their share of a bill you fronted.
So in your budget, count $93 as your utilities spending for the month, and don't count the $186 that comes in as earnings. If you track with the full card charge and leave the paybacks as income, your utilities look three times as high as they are and your income looks $186 higher every month. The two errors cancel in your bank balance, but both of your budget numbers are wrong.
Timing matters too. If the bills post on the 28th and your roommates pay you on the 3rd, the paybacks belong to the month of the bill. Count your $93 share in the month the bill posted, and treat the money that arrives on the 3rd as settling it. We wrote more about this in does a Venmo payback count as income, and about counting only your share of a shared bill in Splitwise and your budget.
If you're one of the roommates paying the account holder, it works the other way. Nothing shows on your card when the bill arrives, and the $93 you send later is your utilities spending for the bill's month.
A short checklist
- List every shared bill and turn any quarterly ones into a monthly number.
- Split the monthly total evenly.
- Agree on fixed extras for any large, obvious differences.
- Prorate by days for move-ins and move-outs.
- Settle once a month with as few transfers as you can.
- In your own budget, count only your share.
If you'd rather not do that last step by hand, Monio links shared bills from Splitwise to the card charge and counts only your share, and money roommates pay you back isn't counted as income.
Questions
How do you split utilities with roommates?
Add up every shared bill for the month, divide it evenly and settle once a month with as few transfers as possible. Split evenly unless there is a large, obvious difference in use, and prorate by days when someone moves in or out partway through a month.
How do you split utilities when a roommate moves in mid-month?
Prorate by days. If a third roommate moves in on the 21st of a 30-day month with a $120 electricity bill, that's 70 person-days, so the new roommate pays $17.14 for 10 days and each original roommate pays $51.43.
How should roommates split internet when one works from home?
Everyone shares the cost of the basic plan, and the roommate who needs faster internet covers the upgrade. If the basic plan is $60 and the faster one is $90, three roommates pay $20 each and the person working from home also pays the $30 difference.
How do I budget utilities when the bills are in my name?
Count only your share as your utilities spending. If the bills come to $279 a month and two roommates each send you $93, your utilities spending is $93, and the $186 they send back isn't income.