We talk about a sublease when the original tenant (sublessor) rents out all or some of the space to a third party (sublessee). A sublet, or sublease agreement, adds someone new to an existing lease.Usually the new person (subletter) replaces someone who is moving out. Sublet and sublease are two different words for the same concept. The suffixes of each word, "let" and "lease," both mean to rent out a property. The difference lies in who ends up in charge of the lease. Subletting is the same as subleasing; the two words are interchangeable. As long as your landlord, or state law, approves, anyone can sublet. A sublet allows direct landlord communication with the subtenant, unlike a sublease, where the legal relationship is between the primary and subtenant. A sublet is when a tenant allows another person, not on the original lease, live in the rental property with the intent of covering all or part of the rent.