Can You Return to the S.S. Anne in Pokemon FireRed?

No. Once the S.S. Anne leaves Vermilion City in Pokemon FireRed, you cannot return to it in that playthrough.

After the ship sets sail, it becomes permanently inaccessible. There is no way to make it return later in the game. The same rules apply in Pokemon LeafGreen.

Why This Moment Feels Uncertain#

The S.S. Anne is one of the first major locations in the game and is part of several one-time locations and missable events in Pokemon FireRed.

You need a ticket to board it.
It contains multiple trainers and items.
You face your rival onboard.
You receive HM01 (Cut) before leaving.

When the ship departs and the harbor is empty, it creates a clear sense that something has changed. For some players, this raises a question:

Is the S.S. Anne gone for good?

What Actually Happens#

After you:

Defeat your rival on the ship.
Obtain HM01 (Cut).
Leave the S.S. Anne.

The ship will sail away permanently.

You cannot:

Re-board the ship.
Revisit any rooms.
Trigger any events there again.

There is no method in Pokemon FireRed to return to the S.S. Anne once it has left.

What This Does NOT Affect#

Losing access to the S.S. Anne does not:

Lock any Gym.
Block story progression.
Prevent you from finishing the game.

It is a one-time location, but not a progression lock.

The S.S. Anne sailing away from Vermilion City in Pokemon FireRed.

In Short#

The S.S. Anne leaves Vermilion City permanently after your visit.

You cannot return to it in the same save file.

However, this does not affect story completion or overall game progression.