The Roommate Money Guide: How to Split Every Shared Expense

Money disputes are the number one cause of roommate conflict. The solution is to agree on a fair splitting method for every shared expense before problems arise. Split rent by room value, utilities by usage, groceries by meals eaten at home, subscriptions equally, and deposits proportionally. This guide walks through each category with exact methods, examples, and free calculator links.

Splitting Rent

Rent is the biggest shared expense and the one most likely to cause friction. The key principle: each person should pay for the value they receive. If one room is bigger, has a private bathroom, or better natural light, that person should pay more.

Best practices:

• Measure each bedroom and calculate rent proportionally by square footage
• Add premiums for private bathrooms (+10–15%), balconies (+5–10%), and extra closet space (+3–5%)
• If incomes differ significantly, consider a hybrid method that adjusts for earning power
• For couples sharing with singles, use a per-room base plus per-person common area adjustment

Splitting Utilities

Utilities include electricity, gas, water, internet, and trash. The simple approach is to split everything equally, but usage differences can make that unfair.

When to adjust the split:

• One roommate works from home and uses significantly more electricity during the day
• Someone has a space heater, window AC unit, or other high-draw personal appliance
• One person takes 30-minute showers while another takes 5-minute showers
• A roommate is away for extended periods (traveling for work, long weekends home)

For internet, equal splitting almost always makes sense since the connection exists regardless of who uses it more. For electricity and water, usage-based adjustments are fairer when patterns differ meaningfully.

Splitting Groceries

Groceries are one of the trickiest expenses to split fairly. A 50/50 split only works if both roommates eat the same amount at home. In reality, one person might cook every meal while the other eats out five nights a week.

Recommended approaches:

1. Separate groceries entirely: Each person buys and stores their own food. Simplest, but misses the savings of buying in bulk and sharing staples like oil, spices, and condiments.
2. Shared staples + separate personal items: Split basics (milk, bread, eggs, cleaning supplies) equally. Each person buys their own specialty items. Best balance of fairness and convenience.
3. Proportional by meals at home: Track how many meals each person eats at home per week and split the shared grocery bill proportionally. If you eat 14 meals at home and your roommate eats 7, you pay two-thirds of shared groceries.

Splitting Subscriptions

Streaming services, internet, and software subscriptions are easy to share and can save each person $50–80 per month. The approach is straightforward:

• Use family plans whenever possible (Spotify Family, YouTube Premium Family)
• Split the monthly cost equally among all users
• Rotate who manages each subscription so one person is not stuck with all the billing
• Keep a shared list of who manages what and how much each person owes monthly

Important: if one roommate moves out, transfer account ownership or cancel their profile. Do not let former roommates continue using shared accounts.

Splitting the Security Deposit

The security deposit is a one-time upfront cost that should be handled carefully:

• Split proportionally to each person's rent share (not always equal)
• Take photos of every room on move-in day as evidence of existing damage
• When one roommate leaves mid-lease, the new roommate pays the departing person directly for their share
• At move-out, common area damage deductions should be split equally; room-specific damage is that person's responsibility

Splitting Chores

Chores are not a financial expense, but they carry real value. An uneven chore distribution creates resentment just as quickly as an unfair rent split. The principles are similar:

• List all recurring chores and estimate the weekly time each takes
• Rate each chore by unpleasantness (1–5 scale)
• Assign chores so total effort (time multiplied by unpleasantness) is equal per person, adjusted for available hours
• Rotate the worst chores so nobody gets stuck with toilets every week
• Re-evaluate monthly since schedules change

Creating a Roommate Financial Agreement

The best time to agree on money matters is before anyone moves in. Write up a simple roommate agreement that covers:

1. Each person's rent amount and due date
2. How utilities, groceries, and subscriptions are split
3. How the security deposit will be handled at move-out
4. What happens if someone is late on payment
5. How rent increases will be handled
6. Guest policies that affect shared costs (significant others staying over frequently)
7. How to handle a roommate leaving mid-lease

This does not need to be a legal contract. A shared Google Doc that everyone signs off on is enough. The act of writing it down prevents selective memory later.