What is Turn (Fourth Street) in Poker?
What Does “Turn (Fourth Street)” Mean in Poker: Detailed Overview
The turn is widely recognized as the "street of truth" in poker. On the flop, players frequently call small exploratory bets with marginal holdings. On the turn, the pot has doubled, and continuing aggression (the second barrel) demands genuine hand strength or a disciplined multi-street bluffing plan.
The arrival of the fourth community card halves remaining draw equity. On the flop, a flush draw had two streets to hit (approx. 35% equity via the Rule of 4). On the turn, only the river remains, reducing your equity to roughly 18% (via the Rule of 2) and rendering passive chasing unprofitable without implied odds.
Second Barrel Strategy & Turn Pot Control
Mastering turn strategy requires evaluating how the turn card alters the balance of range equities. If the turn pairs the board or completes flush/straight draws, the out-of-position player's range may suddenly improve or suffer severe downgrade.
Apply polarization: while a 1/3 pot bet with 100% of your range was viable on dry flops, turn betting ranges should split cleanly into strong value hands and high-equity semi-bluffs. Medium-strength hands should be checked back for pot control.
- Pot size doubles on the turn: bets become substantial relative to remaining stacks.
- Draw probabilities are cut in half: calculate single-street pot odds using the Rule of 2.
- Avoid auto-pilot double-barreling: select bluff cards that improve your perceived range (overcards A, K, Q).
- Use position to check back medium showdown value hands for cheap river showdowns.
Turn Mathematics: Rule of 2 & River Probabilities
Probability of completing a draw from the turn to the river (outs × 2):
Practical Application: “Turn (Fourth Street)”
Scenario: 100bb stacks, Hero opens Cutoff, BB defends. Flop is Q♠ 8♦ 3♣, Hero c-bets 33% pot, BB calls.
Hero Hand: A♠ J♠ (Cutoff) | Board: Q♠ 8♦ 3♣ [Turn: K♠]
Action: BB checks, Hero bets 66% pot second barrel on the turn ($14 into $21), BB folds.
“The King on the turn is an ideal second barrel candidate. It hits Hero's preflop range advantage and gives Hero a royal gutter plus nut flush draw (12 outs). The high-equity semi-bluff maximizes fold equity against BB's middle pairs.”
Pro Tips from 3-Bet Lab
- Target scare cards: turns that bring an Ace or King strongly favor the preflop aggressor and make effective second barrel bluff cards.
- Do not pay full price for gutshots on the turn: 4 outs hit only 8.7% of the time, making calls against standard bets mathematically negative EV.
- Check back vulnerable one-pair hands in position to induce river bluffs from weaker holdings.
Frequently Asked Questions (FAQ)
What is a second barrel in poker?
A second barrel is firing a second consecutive bet on the turn after having already bet the flop as the aggressor. It applies significant pressure to capped defending ranges.
How do you calculate draw equity on the turn?
Multiply your clean outs by 2 (plus a fraction of a percent). For example, 9 flush outs × 2 = 18% (actual: 19.6%). Compare this percentage directly to the pot odds offered by the bet.
When should you check back the turn in position?
Check back when you hold medium-strength showdown value (second pair, weak top pair) that cannot comfortably call a turn check-raise, or when the turn card strongly favors the defender's range.
Master “Turn (Fourth Street)” in Live Practice
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Start Training for Free →Related Terms in Category “Betting Streets”:
- Preflop → Category: Betting Streets
- Flop → Category: Betting Streets
- River (Fifth Street) → Category: Betting Streets
- Showdown → Category: Betting Streets