Have a mattress picked up for free by donating it to a charity or recycling it. Alternatively, ask neighbors and family members if they know someone in need of a mattress.
Various charities offer free pick-up service for mattresses in good condition. Use a website such as DonationTown.org to find a charity in a specific area that offers this kind of service. The Salvation Army may also pick up a mattress, but this varies from one location to another. Call the group at 1-800-728-7825 to find out, as of 2015.
Some mattress recyclers offer pick-up services free, so contact a few local ones to arrange it. When buying a new mattress, some retailers offer a pick-up service for the old one.