M21 — Square Thru / Left Square Thru
Teaching unit M21 of the CALLERLAB (New) Mainstream Suggested Teaching Order, effective
1 September 2026. Prerequisites: Facing Couples,
Square Thru / Left Square Thru
At a glance
| Starting formation | Facing Couples |
| Ending formation | Back-to-Back Couples |
| Timing | 2 beats for one hand; 5 for two; 7 or 8 for three; 10 for four |
| Unit | M21 of 50 |
Animation
▶ Play this call — pause, step and scrub it: Watching the animations.
Dance action
"Complete as many of these actions as appropriate:
- Right Pull By (Square Thru 1 has been completed)
- Face partner and Left Pull By (Square Thru 2 has been completed)
- Face partner and Right Pull By (Square Thru 3 has been completed)
- Face partner and Left Pull By (Square Thru 4 has been completed)"
— CALLERLAB, Mainstream Dance Program Definitions, revised 29 March 2026.
What you do
You start facing another couple, with your partner beside you. The number the caller says is the number of hands you shake before you finish.
- Take your partner's hand. Stand in an ordinary couple handhold in a facing couple, your partner at your side.
- Right Pull By. Step forward, take the right hand of the dancer facing you, and walk past them. Let go as you pass. That is Square Thru 1.
- Face your partner — a quarter turn where you stand — and do a Left Pull By with them. That is Square Thru 2.
- Face that other couple's dancer again and do a Right Pull By. That is Square Thru 3.
- Face your partner again and do a Left Pull By. That is Square Thru 4, and you are done.
Every turn is the same size: a quarter turn in place, never a spin, and you always turn the way that puts your partner in front of you. After each pull by, let go of that hand and offer the other one — that is the whole trick of the call. The two couples finish back to back, facing out.
Timing
The manual gives a different figure for each length: Square Thru 1 is 2 beats, Square Thru 2 is 5, Square Thru 3 is 7 or 8, and Square Thru 4 is 10. Ten beats is two and a half bars of music, which is why callers usually say the number out loud — you always know how many hands are coming. See Timing and music.
Styling
"With the Pull By the hands are released as dancers pass each other so as to avoid guiding one
another to turn the wrong way. As in Right and Left Grand, dancers should make their opposite hand
available for their next Pull By (or the next call)."
— CALLERLAB, Mainstream Dance Program Definitions, revised 29 March 2026.
Let go early. A pull by is a handshake on the move, not a grip that steers anybody. The manual adds that on each pull by, "as dancers pass they should be facing Head or Side walls" — in other words you pass square to the walls, not diagonally.
Restrictions
The manual is firm about the left-handed version:
"Left Square Thru (N,O,P,Q) is similar to Square Thru (N,O,P,Q) except that it is started with the
left hand and hands are alternating thereafter; the word "Left" is required."
— CALLERLAB, Mainstream Dance Program Definitions, revised 29 March 2026.
So Left Square Thru is not a mirror you may choose for yourself: the caller must say the word "Left", and the first hand you take is the left. If all you hear is "Square Thru", the first pull by is with the right hand. The manual's own example is "Heads Lead Right, Circle to a Line, Left Square Thru 4, Left Allemande". See Mainstream restrictions.
Common faults
| What happens | Why | The fix |
|---|---|---|
| You finish beside your partner instead of facing them | You turned the wrong way, or not at all, after the pull by | After every pull by, turn a quarter turn in place until your partner is in front of you |
| You lose count and the square breaks down | You stopped listening after the number | The caller says the number once, at the start. Say it back to yourself and count each pull by |
| You grip hands and drag your partner round | Holding on through the pass | Release as you pass. The pull by is a handshake, not a tow rope |
| The couples finish side by side rather than back to back | One of you turned a half turn instead of a quarter | Every turn in Square Thru is a quarter turn |
Where you meet it
Square Thru arrives in Class 6, right after Bend the Line, and never leaves. It is the standard way to move two facing couples past each other and back to back, so it turns up in Zeroes, in singing calls and in almost every tip you will ever dance.
Related calls
- Pass Thru — one pull by, and you keep going. See M7.
- Right and Left Thru — a pull by followed by a Courtesy Turn. See M10.
- Star Thru — turns a facing pair into a couple without a pull by. See M18.
- Slide Thru — the same kind of one-move pass. See M28.
Also called / formerly
Square Thru has always been called Square Thru, but the shorter lengths have their own names: the manual records that "Half Square Thru" may be used for Square Thru 2 and "Square Thru Three-Quarters" for Square Thru 3, while plain "Square Thru" means four hands. Longer versions are allowed too — "Square Thru 5" — and "Square Thru, on the Third Hand …" means the third pull by blends straight into the next call.
Manual source: Mainstream Dance Program Definitions, revised 29 March 2026, page 55. Reproduced under the permission in sources and attribution.