In a joint tenancy mortgage, co-owners possess equal interest in the property and enjoy the right of survivorship, meaning if one owner passes away, their share of the property automatically transfers to the surviving co-owners. Conversely, a tenants in common mortgage allows co-owners to hold unequal shares of the property, with no right of survivorship. When one owner dies, their share passes on as per their will or estate plan, not automatically to the remaining owners. Understanding these differences is vital when considering a partial interest mortgage.