A top out occurs when:

• a tetromino cannot be placed at least partially within the play zone.
• garbage pieces are sent, pushing the top pieces above the spawn zone.

Top outs result in a game over.

Loss condition

There are several variations of what constitutes a top out:

• Block out: a piece is spawned overlapping at least one block in the playfield
• Lock out: a piece locks when it is entirely out of bounds (that is, in the vanish zone above the ceiling)
• Partial lock out: a piece locks when it is partially out of bounds, even if it would clear a line
• Garbage out: After lines are cleared and garbage is added, a block remains out of bounds

Different games have used different combinations of these conditions:

This list is incomplete.

• Tetris (NES, Nintendo): a piece locks overlapping at least one block, but in some cases it is possible to move or rotate out of such a situation
• Tetris (Game Boy): Similar to NES Tetris, but slightly more lenient in ways that aren't fully understood
• Dr. Mario, Tetris and Dr. Mario, Puyo Pop, Super Puzzle Fighter II, Kirby's Star Stacker: block out
• Bombliss: garbage out
• Tetris (Atari), Tetris (NES, Tengen), The New Tetris, and Tetris DS (push mode): partial lock out or garbage out
• Tetris Attack: garbage out; in multiplayer mode, evaluation is delayed by a split second
• Tetris DS (standard mode and mission mode) and most other recent games: block out or lock out