Set out fair and legally binding terms as you lease your Ontario premises. Cover crucial aspects with our Sublease Agreement Sample Ontario template.A Sublease Agreement is a contract that outlines the terms of a sublease between an existing tenant and a subtenant. A sublease agreement is a legal document that allows a tenant to sublet a property to someone else (subtenant). Also known as subletting. Edit, sign, and share sublease agreement online. No need to install software, just go to DocHub, and sign up instantly and for free. How do I fill this out?