Good question! A renters policy is less expensive because it covers less than a homeowners policy does. A renters policy primarily covers a tenant’s personal property and liability. Since a renter doesn’t own the home, they are not responsible for the physical property of the home and other structures; the landlord should cover these on a separate policy.
For more information about the cost of renters insurance, check out this article: What Is the Average Cost of Renters Insurance?.