Living with roommates is how most people afford their first place, and it works fine right up until the money gets fuzzy. Someone's late on their share, the electric bill sits unpaid in one person's name, someone moves out mid-lease and everyone else eats the cost. Almost every one of those fights traces back to a decision nobody made at move-in. Make them up front, on purpose, and the apartment stays a home instead of a slow-motion argument.

Who's on the matters more than anything

Most leases make co-tenants jointly and severally liable, which is legal language for: each person on the lease owes the entire rent, not just their slice. If your roommate stops paying, the landlord doesn't care about your internal split; they can come after you for all of it, and a missed month can land on every tenant's record. The flip side matters too. A roommate who's not on the lease has no tenant rights, can be asked to leave by the actual tenants, and technically may not even be allowed to live there. Before anyone signs anything, read Renting 101: Your Rights as a Tenant so everyone knows what the lease actually commits them to.

Split rent by what people get

An even split is only fair when the rooms are even. If one bedroom is twice the size or has its own bathroom, splitting the rent equally means somebody is subsidizing somebody else, and that resentment compounds monthly. Do it once, with numbers: on a $2,100 three-bedroom, the big room with the private bath might pay $800 while the two smaller rooms pay $650 each. There's no single correct formula (some houses go by square footage, some just agree on premiums room by room). What matters is that everyone calls it fair out loud before move-in, because renegotiating in month seven is much harder.

Utilities: whose name, whose credit

Utility accounts need a name on them, and that name is the one that matters to the company. If the internet bill in your name goes unpaid because a roommate never sent their share, the late payment is yours alone. Two habits keep this fair. First, spread the accounts around: one person holds electric, another internet, so no single person carries all the risk. Second, treat reimbursement like a bill, not a favor: shares are due by a set day each month, sent by , no chasing required.

Write the shared-costs doc

It sounds overly formal for friends. It's the opposite: writing things down is what keeps you friends, because nobody has to remember, argue, or guess. One page covers it:

  • The rent split, per person, and the date each share is due.
  • Who holds each utility account and how shares get paid back, by when.
  • Shared stuff: how groceries, supplies, and jointly bought furniture get handled, including who keeps what if you split up.
  • The leave-early terms: how much notice someone gives, and what they owe until a replacement is found.

Everyone signs it and keeps a copy. It isn't a lease and a court probably won't enforce it, but that was never the point. The point is that the argument you'd have in month seven already got settled in writing on day one.

When someone leaves early

This is the scenario that wrecks the most friendships, so decide it in advance. The lease doesn't shrink because one name walks out; the remaining roommates still owe full rent. The usual fixes: the leaver keeps paying their share until a replacement is found, helps find that replacement (landlords typically must approve a new tenant), or subleases if the lease allows it. Agree on which applies before anyone needs it. The needs a plan too, since landlords often return it as one check at the very end of the lease. The clean approach is to have the incoming roommate buy out the departing one's deposit share, and How to Get Your Security Deposit Back covers making sure that money comes back at all.

The landlord sees one household, not four friends with separate arrangements. Everything inside the household (splits, shares, buyouts) is only as solid as what you've agreed to in writing with each other.