Climb via SID or maintain on an IFR clearance

July 10, 2026 · FAA phraseology · JO 7110.65 4-3-2 · AIM 5-2-9 · examples from current charts

Every IFR departure clearance answers the same five questions — the classic CRAFT mnemonic: Clearance limit, Route, Altitude, Frequency, Transponder. The altitude line is where most trainees slip, because what you say depends on how the SID is charted, not on habit. Since the FAA’s 2014 “climb via” change, there are exactly three possibilities.

Case 1 — published top altitude: “climb via SID”

Open the ZZOOO FOUR departure at San Diego (KSAN). The chart box says TOP ALTITUDE: JETS FL230 / TURBOPROPS 15000, and the route carries its own crossing and speed restrictions. Everything the pilot needs is printed — so the controller assigns none of it:

No “maintain”. The SID is the altitude instruction: the pilot climbs to the published top altitude and meets every published restriction on the way. Adding “maintain FL230” on top of “climb via SID” is wrong — and saying “maintain 5000” instead would quietly cancel restrictions the procedure designer put there.

Case 2 — restrictions published, top “assigned by ATC”: “climb via SID except maintain”

Some SIDs publish crossing restrictions but leave the top altitude open — the chart reads TOP ALTITUDE: ASSIGNED BY ATC. San Diego’s PEBLE SIX is one: it requires crossing MELDY at or above 14 000, but ATC owns the stop altitude. The pilot still has to fly the restrictions, so “climb via” stays — with the altitude bolted on:

Read that as: “fly the SID’s lateral path and meet its restrictions, and your top altitude — the thing the chart left blank — is 14 000”.

Case 3 — vector SIDs and hybrids: plain “maintain”, never “climb via”

A radar-vector SID has no route to fly from the runway — the KENNEDY FIVE at JFK is the classic example (“fly assigned heading, radar vectors to assigned route”). Many SIDs are hybrids that start the same way: every San Antonio (KSAT) departure begins “climb on assigned heading for vectors to…”, then joins a charted track. Per the FAA’s Climb Via guidance, “climb via” applies to neither. ATC assigns the altitude directly — usually the value printed in the route description:

Same story at KSAT (“maintain 5000” is printed on every SID there) and at Boise, where the BOISE THREE’s own text climbs you to 16 000 on runway heading.

How do I know which case I’m in?

The readback: what you should hear

“Climb via” is one of the few phrases a pilot must read back verbatim. Listen for it — a readback of “maintain flight level two three zero” after you said “climb via SID” is a readback error, and it’s on you to catch it:

Common mistakes

• “Maintain 5000” on a climb-via SID. This cancels the procedure’s published restrictions. If the top altitude is published, say “climb via SID” — nothing more.
• “Climb via SID” on a vector SID. There is no published route to climb via. Assign an altitude.
• Forgetting the transition. “ZZOOO Four departure, Gila Bend transition, then as filed” — the transition is part of the route.
• “Climb via SID except maintain” when the top is already published. “Except” exists precisely for charts whose top altitude is ATC-assigned.