When the FCC's Wireless Local Number Portability (WLNP) mandate goes into effect on November 24, cell-phone users will be able to switch service to other carriers and keep their numbers for the first time. According to the FCC, nearly half of the US population owns a cell phone, so carriers might see a glut of cell-phone users looking for better deals after the mandate takes effect. CellUpdate.com—a Web site dedicated to helping cell-phone users save money—suggests tips for selecting a plan that best fits your needs and lowering your monthly bill, such as knowing your usage needs before signing up for a plan, knowing where you make your calls, and being aware of charges for changing your plan. The Web site also has daily updates about cellular news and tips on the charges your carrier might include in your plan's fine print.