Definition
The pilot action of formally closing an active IFR flight plan with Air Traffic Control, terminating IFR services and the associated ATC clearance. Cancellation can occur airborne once the flight is in VMC and outside Class A airspace, or on the ground after landing at an airport without an operating control tower. At a towered airport, landing automatically closes the IFR flight plan; no separate cancellation is required.
Plain English
Telling ATC you no longer need to be on your IFR flight plan. Once you cancel, ATC stops providing IFR services and you continue under visual flight rules — or, if you have already landed at a non-towered airport, you are simply closing out the flight plan so no one launches a search for you.
Context Anchor
You encounter this during arrivals, especially when breaking out into visual conditions before landing or after landing at an airport without an operating control tower.
Derivation
Cancel comes from a Latin word meaning “to cross out.” In this aviation use, it does not mean the flight itself is called off; it means the IFR flight plan and IFR handling are ended.
Why Pilots Care
Proper cancellation ends IFR separation services, allows transition to VFR, and prevents unnecessary use of ATC resources while maintaining safety.
Grounding Statement
Cancelling an IFR flight plan is the point where ATC stops treating the flight as operating under IFR.
Intuition Check
Do not read “cancelling” as cancelling the whole trip. Here it means ending the IFR part of the flight plan and the IFR service connected to it.
Example Sentence 1
After breaking out into clear skies twenty miles from the destination, the pilot called Center and said, "Cancel IFR," then continued VFR to the airport.
Example Sentence 2
After landing, the pilot contacted the tower to complete cancelling IFR flight plans as required by regulations.