The Baltimore CASH Campaign this tax season will have 18 sites in Baltimore and two in Baltimore County where tax filers can get free tax preparation. The service is available to singles with income last year under $25,000 and families that earned less than $49,000. The nonprofit announced the sites and details Tuesday. One new feature is that filers will have the option to have all or some of their tax refunds go into U.S. Savings Bonds. Four of the sites also will be able to help families fill out the FAFSA form that must be sent in to receive federal student aid. Call First Call for Help at 410-685-0525 to find sites offering free tax preparation.