Check Your Lease First
Almost every lease says something about subletting, and that language controls in most situations regardless of what state law would otherwise allow. Common versions include: subletting is banned outright, subletting is allowed only with the landlord's prior written consent, consent can't be unreasonably withheld, or the lease says nothing about it at all.
What Subleasing Actually Means
When you sublease, you rent your apartment to someone else (the subtenant) while you stay on the original lease. You're still responsible to your landlord for the rent and the condition of the unit — the subtenant pays you, not your landlord, so if they don't pay or damage the place, that's between you and your landlord regardless of your side arrangement with the subtenant. If your subtenant stops paying, you're still expected to pay your landlord in full and on time, then pursue your subtenant separately for what they owe you, the same as any other debt between two private parties — your landlord's only relationship is with you.
Assignment Is a Different Thing
An assignment transfers your entire lease to someone else, and you're generally released from further obligation once it's accepted, depending on your lease's terms. A sublease keeps you legally on the hook the whole time. Leases frequently treat these very differently — some allow one but not the other — so don't assume permission for one covers the other. If your goal is to leave for good and hand the apartment off entirely, an assignment (where your landlord agrees to it) is usually the cleaner fit; if you plan to come back, or you're only gone for part of the lease term, a sublease is the one that actually matches what you're trying to do.
What to Put in a Sublease Agreement
However your lease treats subletting, put the arrangement with your subtenant in writing regardless. A basic sublease agreement should cover the rent amount and due date, the exact dates it covers, who's responsible for utilities, what happens to the security deposit you collect from the subtenant, and what happens if the subtenant needs to leave before the sublease period ends. Say your rent is $1,800 a month and you're subletting for the four months you'll be away — spell out whether the subtenant pays you $1,800 directly or some other split, and what recourse you have if a payment is late, since your landlord will still look to you either way.
If Your Lease Requires Consent
Where a lease requires the landlord's written consent, some states let the landlord set reasonable conditions, like requiring the subtenant to pass a credit or background check similar to what you went through. Whether the landlord can refuse for any reason, or only a reasonable one, depends on your lease's exact wording and your state's law — this isn't consistent everywhere. As an example of how specific this gets: California has a statute letting a landlord's consent be withheld only for reasonable cause, or freely at the landlord's discretion, depending on what the lease itself says — but that particular statute applies only to non-residential leases, not apartments (Cal. Civ. Code §§ 1995.020(b), 1995.250). That's a useful reminder that a rule you read about for commercial leases, or for a different state, may not carry over to your own residential lease at all.
If Your Lease Is Silent
If your lease says nothing about subletting, some states give you a right to sublet unless the lease specifically prohibits it, while others default the other way. There's no nationwide default, so this is genuinely a check-your-state situation rather than something with a single answer.
Subletting Without Permission
If you sublet in violation of a clause requiring consent, you're technically breaching your lease, which can be grounds for eviction or damages even if your subtenant pays rent on time and takes care of the place. It's almost always worth asking first, in writing, even if you expect the answer to be no — a documented refusal at least tells you where you stand, and it protects you if a dispute over the unauthorized subtenant comes up later. This exposure is one of the biggest practical differences between having a subtenant and having a roommate who's actually on the lease, and it's worth thinking through before you agree to a sublease with someone you don't know well.
Protecting Yourself
Get any sublease agreement in writing, including the rent amount, dates, and what happens if the subtenant doesn't pay or damages the unit. Honestkey can flag your lease's subletting and assignment clauses so you can see what your lease actually says before you advertise the room.