Insurance Services Office Letters

Many times an insurance company will ask for the distance from a property to the closest fire station and fire hydrant. Some underwriters utilize the Insurance Services Office (ISO) for determining risk to a particular property.

How to get an ISO letter

  • Submit your request in writing, by either fax or e-mail
  • Include in the request:
    • Insured's address
    • Your name
    • Your phone number
  • Check if a County fire hydrant is near your home
    • Enter your address in the search box
    • Hydrants are marked with red dots for County and yellow dots for private


  • For more information in ISO letters, call (813) 744-5541
  • For questions or more information on hydrants, please email