IFR flight requires separation minima to be applied by ATC. When an aircraft reverts to VFR (cancels IFR), the pilot takes on the responsibility for separation from other traffic. By cancelling IFR, you relieve ATC of the restrictions incumbent with instrument traffic requirements.

To "cancel IFR" (Instrument Flight Rules) means that a pilot is officially informing Air Traffic Control (ATC) that they are transitioning from flying under instrument guidance to flying under VFR (Visual Flight Rules). This typically happens when a pilot is approaching their destination and has established visual contact with the airport or the ground in clear weather conditions. Once IFR is cancelled, the pilot is no longer under the strict "positive control" of ATC for separation from other aircraft; they become responsible for their own navigation and for "seeing and avoiding" other traffic. In 2026, canceling IFR is a common way to speed up an arrival at a non-towered airport, as it "closes" the flight plan and frees up the airspace for other instrument arrivals. However, a pilot must be certain that they can maintain the required visual minimums (ceiling and visibility) before making this call, as they lose the guaranteed separation services provided by the IFR system.