The simplest way to split expenses with roommates is an even split on everything, but simplest isn't always fairest. There are three methods that work, and most apartments end up using a mix. What matters is picking your system once, at the start, instead of renegotiating over every receipt.
Method 1: Even split
Every expense divides by the number of roommates. Simple, transparent, nobody feels played. This is the right call for internet, electric, gas, and shared household supplies.
Where it breaks: when the bedrooms are wildly different, or when someone is barely home. The person in the 90-square-foot room who travels for work every other week will not love paying the same electric bill as the one camped in the living room with the AC running.
Method 2: By room (for rent)
Rent splits by what each room is actually worth. The room with the private bathroom and the walk-in closet pays more. The one next to the kitchen with the window facing a wall pays less. Settle this split once, on lease-signing day, and ideally before anyone claims a room, so people choose with the price in front of them.
There are online rent-split calculators that do this by square footage and features if you want a neutral starting number. Then adjust by feel and shake on it.
Method 3: By usage
For expenses only some roommates actually consume. Two out of three signed up for the building gym? Only those two split it. One roommate is vegetarian and the grocery run includes meat? Split the receipt accordingly. It takes slightly more tracking, but it kills the quietly corrosive feeling of paying for other people's stuff.
Why the spreadsheet dies in February
All three methods only work if expenses actually get recorded. And there's the problem: everyone updates the spreadsheet for two weeks, then someone forgets one receipt, then another, and by March nobody remembers whether you paid Maya back for that Costco run or not.
In SHULAM! each roommate logs an expense in seconds, picks how it splits (evenly, by percentage, or among only some of you), and everyone's balance updates on its own. Grocery receipts don't even need typing: snap a photo and the app reads the items and amounts. At the end of the month you see one clean line - who owes whom and how much. Venmo it, mark it paid, done.
FAQ
What if one roommate earns way more than the others?
Splitting by income almost never works between roommates. It requires disclosing salaries and it breeds resentment. Split by room and by usage instead, and let income differences show up in who picks the bigger room.
How do we handle a roommate who keeps forgetting to pay?
Set a fixed settle-up day, like the 5th of every month. A recurring reminder from the app does the chasing for you, which is a lot less awkward than texting "hey, that transfer?" for the third time.
Should we bother splitting small stuff like paper towels?
Yes, especially the small stuff. A $6 expense isn't worth a fight, but twenty of them a month is real money. When logging takes ten seconds, there's no reason to let it slide.
SHULAM! is a free app for running a shared home: expenses, groceries, fridge, and chores in one place. Available on the App Store and Google Play. Download it and start splitting fair.