Definition
An ATC instruction directing a pilot to adhere to all published altitude and/or speed restrictions depicted on a Standard Instrument Departure (SID), Standard Terminal Arrival (STAR), or other charted procedure. The pilot must meet each crossing altitude and speed exactly as charted, even if previously cleared to a different altitude or speed.
Plain English
ATC is telling you to fly the procedure exactly as printed on the chart, hitting every altitude and speed shown along the way.
Context Anchor
Heard in air traffic control clearances, especially when flying a published departure, arrival, or assigned route with altitude or speed limits.
Derivation
Comply comes from a Latin root meaning to complete or carry out. Restriction comes from a Latin root meaning to hold back or limit. Together, the phrase means to carry out the clearance while still staying within the stated limits.
Why Pilots Care
Failure to comply can result in loss of separation, airspace violations, or enforcement action.
Grounding Statement
If a published procedure says to be at a certain altitude by a certain point, this instruction means that limit still applies.
Intuition Check
Do not hear this as a general reminder to be careful. In this context, it means the specific limits attached to the clearance or procedure must still be followed.
Example Sentence 1
Cleared to descend via the KAYOH THREE arrival, comply with restrictions.
Example Sentence 2
Always comply with restrictions on the departure procedure to avoid terrain.