Yes, you can fly IFR (Instrument Flight Rules) in Class E airspace in 2026. In fact, most en route IFR flight occurs in Class E, which extends from 1,200 feet AGL (or 700 feet AGL in transition areas) up to, but not including, 18,000 feet MSL (the start of Class A). In Class E, IFR aircraft are under the control of Air Traffic Control (ATC) and must have an IFR flight plan and clearance. While VFR (Visual Flight Rules) aircraft can fly in Class E without a clearance or radio communication—provided they maintain specific cloud clearances and visibility—IFR aircraft are fully separated from one another by ATC. This "controlled" nature of Class E ensures that instrument traffic can transition safely between the highly controlled terminal areas (Class B, C, and D) and the high-altitude Class A corridors. It is important to remember that while ATC separates IFR from IFR, the pilot remains responsible for "see and avoid" regarding VFR traffic in Class E during visual conditions.