Subletting, also known as subleasing, involves renting out a property or a portion of it that you are currently leasing, to a new tenant. Subletting is a real estate arrangement where a tenant leases their rental property or part of it to another individual, known as a subtenant.A sublease is an agreement where someone takes over part or all of an existing lease. This type of lease involves at least three parties. Here's some language for a sample letter requesting sublet permission. Use it in part or full when submitting your proposal. We created this community to make the process of finding a new home, tenant, or roommate, just that bit easier. A sublease agreement is a legal contract signed between a tenant and a third party allowing the latter to rent out the entire property or any part of it. A sublet is when a landlord is re-renting property from the main tenant to a new tenant. The new tenant takes over the main tenant's lease.