Splitting rent with roommates sounds simple until you're in a three-bedroom apartment where one room has an ensuite bath, another has a walk-in closet, and the third is half the size. Or when one roommate earns three times as much as the others. There's no single "correct" way to divide rent — but there are three established methods, and the best one depends on your specific situation and your relationship with the people you're living with.

Method 1: Equal Split

Simplest approach
Divide total rent by number of roommates
Each roommate pays the same amount regardless of room size, income, or any other factor. This is the easiest to calculate, the easiest to explain, and eliminates any perception of unfairness through complexity. It works best when rooms are similar in size and quality.
Equal Split — $3,000/month, 3 roommates
Roommate A$1,000
Roommate B$1,000
Roommate C$1,000
Total$3,000

Method 2: Split by Room Size

Most common fair approach
Each roommate pays proportional to their room's square footage
Calculate each bedroom's square footage as a percentage of total bedroom square footage combined, then apply that percentage to the total rent. Adjustments can be made for ensuite bathrooms, closet size, windows, or other features that add value to a specific room.
Room Size Split — $3,000/month
Room A: 180 sq ft (40%)$1,200
Room B: 150 sq ft (33%)$990
Room C: 120 sq ft (27%)$810
Total$3,000

Method 3: Split by Income

Income-proportional
Each roommate pays based on their share of combined income
This method ensures housing costs represent a similar percentage of each person's income. It requires everyone to disclose their earnings — which some people are uncomfortable with — but it's the most equitable approach when there are significant income differences among roommates.
Income-Based Split — $3,000/month
Roommate A earns $5,000/month (45%)$1,350
Roommate B earns $4,000/month (36%)$1,080
Roommate C earns $2,200/month (20%)$600 (+ $30 shortfall)
Total$3,000

Which Method Should You Use?

The best method is the one every roommate agrees to before moving in — get it in writing and revisit it if circumstances change. Use the Rent Split Calculator to run all three methods instantly and share the results with your roommates before committing to a split.

What Else to Decide Before Moving In

These conversations are uncomfortable before moving in and significantly worse after. Have them early, agree in writing, and your roommate relationship will be far smoother throughout the lease.