Is there a waiting period for flood insurance to become effective?

Yes. There is a 30-day waiting period before flood coverage goes into effect. The effective date of a new policy will be:

• 12:01 a.m., local time, on the 30th calendar day after the application date and the presentment of premium.

However, there are exceptions in which the 30-day waiting period does not apply:

• In connection with making, increasing, extending, or renewing a loan, whether conventional or otherwise, flood insurance that is initially purchased in connection with the making, increasing, extending, or renewal of a loan shall be effective at the time of loan closing, provided that the policy is applied for and the presentment of premium is made at the time of or prior to the loan closing.
• In connection with lender requirement, the 30-day waiting period does not apply when flood insurance is required as a result of a lender determining that a loan on a building in an SFHA that does not have flood insurance coverage should be protected by flood insurance. The coverage is effective upon the completion of an application and the presentment of payment of premium.
• When the initial purchase of flood insurance is in connection with the revision or updating of a Flood Hazard Boundary Map (FHBM) or Flood Insurance Rate Map (FIRM): During the 13-month period beginning on the effective date of the map revision, the effective date of a new policy shall be 12:01 a.m., local time, following the day after the application date and the presentment of premium. This rule applies only where the FHBM or FIRM is revised to show the building to be in an SFHA when it had not been in an SFHA.