PLO Post-flop Raise/3bet Pot Size Calculation: Why the 3x Rule is Wrong?

In Pot-Limit Omaha (PLO), correctly calculating pot-sized raises postflop when facing a raise or 3-bet is fundamental. Recently, a player on the Reddit poker community encountered a calculation confusion:

Initial pot $45. V1 bets pot ($45). V2 re-raises pot ($180). V1 wants to re-raise pot again. How much should V1 bet?

Common Mistake: The 3x Rule

Many players use the shortcut formula "3x the last bet + the previous bet", i.e., 3×$180 + the earlier bet of $45 = $585. However, this calculation is incorrect in PLO because it ignores the change in pot size after calling.

Correct Calculation Method

According to official PLO rules — first call, then raise the current pot size:

1. V1 has bet $45. Facing V2's $180 bet, V1 must first call $135 ($180 - $45). At this point, the pot becomes: initial $45 + V1's $45 + V2's $180 + V1's call of $135 = $405.
2. Then V1 raises a pot-sized amount, i.e., $405.
3. Therefore, V1's total bet is: call $135 + raise $405 = $540.

This matches the answer given by AI (Claude) and is confirmed by earlier forum discussions.

General Formula

When facing a pot-sized raise, the general formula for a pot-sized re-raise is:

Pot-sized raise = 3 × the bet faced + your own previous bet in the pot? No, the correct formula is: Total bet = (current pot + 2 × your own bet) + ? Actually, a more straightforward calculation is:

• First calculate the pot after calling: pot before call + the bet faced (or the difference).
• Then raise that pot.

To avoid confusion, it is recommended to calculate manually step by step, especially in complex multi-way pots.

Conclusion

In PLO, pot-sized raise calculations postflop (or preflop) should not rely on the "3x rule", but should follow the standard "call then raise pot" process. Mastering this principle can avoid strategy errors and is crucial, especially in high-variance pots.