According to ICAO Annex 11 (Air Traffic Services), a Flight Information Service (FIS) is a specialized service provided to give advice and information useful for the safe and efficient conduct of flights. Unlike air traffic control, which provides specific separation instructions, an FIS provides "pertinent information" such as SIGMET and AIRMET weather alerts, information on volcanic ash or radioactive materials, changes in the serviceability of navigation aids, and updates on aerodrome conditions (like snow or ice). In 2026, FIS units operate globally within specific Flight Information Regions (FIRs). Pilots typically contact a Flight Information Centre (FIC) or an Aerodrome Flight Information Service (AFIS) to receive these updates. This service is essential for VFR (Visual Flight Rules) pilots, offering assistance with position reporting, transponder checks, and warnings about restricted or dangerous airspace, ensuring that even aircraft outside of controlled airspace have access to critical safety data.