Tenants in Washington must obtain explicit written consent from their landlord before subleasing a rental property. Here is a sample sublease agreement you can fill out or use as a template.The document will lay out the stipulations of the agreement, including the rent amount, a copy of the original lease agreement, and more. If written consent is not obtained from the landlord within five (5) days, this Agreement shall terminate within any money paid to the Tenant to be refunded. Do you want a new subtenant living in your property who you didn't select? Find Out What To Do If Your Tenants Ask To Sub-Lease in Seattle, WA. 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. Have back rent and need assistance? From renting a room in a house to subletting an unused basement, any property currently being leased can be sublet if the landlord allows it. Residential Rental Forms.