Short answer
Split rent by room size (a percentage each, based on square footage) if the rooms are noticeably different, otherwise evenly. Split utilities and internet evenly unless someone uses much more. Split shared groceries evenly or by custom amounts. Write the rules down, keep every bill in one place, and settle on the same day each month.
Splitting rent by room size: a worked example
Rent is $2,400 a month. The three bedrooms are 180, 150 and 120 sq ft (450 sq ft in total). Each person pays their room's share of the total:
| Room | Size | Share | Rent |
|---|---|---|---|
| Largest (with ensuite) | 180 sq ft | 40% | $960 |
| Middle | 150 sq ft | 33.3% | $800 |
| Smallest | 120 sq ft | 26.7% | $640 |
| Total | 450 sq ft | 100% | $2,400 |
Some households first split the cost of shared space (kitchen, living room) evenly and apply room size only to the bedrooms. Either is fine, as long as everyone agrees before signing the lease.
Rent of $2,400 split by room size
Household bills
| Bill | Usual split | When to change it |
|---|---|---|
| Internet | Evenly | Rarely |
| Electricity and gas | Evenly | Someone works from home all day, or runs a space heater: agree a percentage |
| Water | Evenly | Rarely |
| Shared groceries | Evenly | Diets differ a lot: custom amounts, or buy separately |
| Streaming services | Only those who use them | Always opt in, never assumed |
A system that avoids arguments
- Write the rules down in a shared note: rent split, which bills are shared and how, and the settle-up day.
- Whoever pays a bill saves it (the PDF or a photo) to one household folder.
- Work out each person's share and send it the same day.
- Settle on a fixed day each month, and tick off who has paid.
These are common approaches, not legal or financial advice. Check who is named on the lease and on each utility account, because that person is usually responsible for paying it in full.
New in EZ Save: share a photo of a bill or receipt and EZ Save spots it automatically, reads the total on your iPhone or iPad, and splits it evenly, by percentage or by custom amounts. Tick people off as they pay, and settle up several bills at once. Friends don't need the app. See how it works.
On a MacBook? EZ Save has a native Mac app. Drag the lease PDF or a utility bill up to the notch, pick a folder from the panel that drops down, and it’s saved to the same library as your iPhone. Free, on MacBooks with a notch. See it in action →
Frequently asked questions
Is it fair to split rent evenly?
How do you split rent by room size?
How should roommates split utilities?
Is there an app for splitting bills with roommates?
Keep every bill in one place
Save receipts, bookings and photos into folders with EZ Save today. Bill splitting from a photo is free.