Under Visual Flight Rules (VFR) in the United States and many other jurisdictions in 2026, filing a flight plan is not legally mandatory for most domestic flights in "uncontrolled" or "standard controlled" airspace. However, it is considered a critical safety best practice. A VFR flight plan acts as a "safety net"; when you "open" the plan with Flight Service, you provide a designated arrival time. If you do not "close" the plan within 30 minutes of that time, search and rescue (SAR) operations are automatically triggered. There are, however, specific exceptions where a VFR flight plan is required: for example, when crossing international borders, when flying through an Air Defense Identification Zone (ADIZ) (which requires a Defense VFR or DVFR plan), or when operating in certain "Special Flight Rules Areas" like the Grand Canyon or Washington D.C. Even if not required, modern pilots use tools like ForeFlight to file VFR plans electronically, as it simplifies the process of receiving "Flight Following" (radar transitions) from Air Traffic Control, significantly increasing safety during cross-country treks.