If your landlord decides to deny your sublet request, the denial must be reasonable. Your landlord cannot unreasonably withhold consent to sublease.You are entitled to request permission to sublet from the owner, and the owner may not unreasonably refuse such permission. A tenant renting a residence may not assign his lease without the written consent of the owner, which consent may be unconditionally withheld without cause. If you have a lease for a set term, like one year, you can sublet with or without your landlord's permission, unless they prohibit this in the written lease. The procedure for subleasing is quite complicated. This booklet explains many of these laws you need to know and provides resources where you can find more information about landlord and tenant issues. If you have a lease for a set term, like one year, you can sublet with or without your landlord's permission, unless they prohibit this in the written lease. In New York, tenants who wish to sublet their commercial lease must obtain written consent from their landlord. Sublease agreement: Permits tenants to rent part or all of the property to another person, subject to landlord approval.