Definition
An ATC clearance instruction requiring the pilot to cross a specified fix at an altitude equal to or higher than the altitude stated, but never below it. The pilot may choose any altitude at or above the stated value when crossing the fix, subject to other clearance limits.
Plain English
When you fly over this point, you must be at this altitude or higher — not lower.
Context Anchor
Used in ATC clearances, instrument procedures, arrivals, and descent planning when an aircraft must meet a minimum altitude at a specific point along its route.
Why Pilots Care
Maintains required terrain or traffic separation while allowing flexibility above the floor.
Grounding Statement
Picture your route crossing a named point on the chart; at that moment, your altimeter must show the assigned altitude or something higher.
Intuition Check
Do not read “at or above” as “exactly at.” It means the stated altitude is the lowest altitude allowed at that fix.
Example Sentence 1
ATC issued the clearance: 'Cross JONES at or above six thousand,' so the pilot planned the descent to level off at 6,500 over the fix.
Example Sentence 2
The amended clearance said cross the intersection at or above 4000 feet to stay above the MOCA.