To amend the National Flood Insurance Act of 1968 to provide for a phased-in increase of chargeable premium rates for properties affected by updated Flood Insurance Rate Maps.

Amends the National Flood Insurance Act of 1968 to provide that an increase in the risk premium rate charged for covered properties mapped into a higher-risk flood zone as the result of an update to a Flood Insurance Rate Map (post-FIRM properties) shall be limited to an annual increase for 5 years of 20% per year of the difference between: (1) the risk premium rate otherwise chargeable pursuant to such update; and (2) the chargeable risk premium rate for such property that existed before such update.