Split Decisions on Pairs at Blackjack

23 May 2021

By John Grochowski

Blackjack players refer to "the basic strategy chart," but there's is not one chart.

Charts for one, two and four or more decks differ. For each number of decks, there are separate charts depending on whether the dealer hits or stands on soft 17. And on a few special-case hands, there are footnotes.

Among the footnote hands are pairs of 2s and 3s. Each carries a "notation against certain dealer
up cards." which stands for split or hit, and the dividing point is whether you are allowed to double down after splitting pairs. If doubles after splits are in play, then there's extra potential benefit in splitting the pairs.

Deuces and treys aren't the only pairs that get the Ph strategy notation, but the best plays and reasons behind them are similar for these low cards. We can catch up on other Ph pairs another time, but for this week, let's focus on 2s and 3s.

For each of those pairs, let's focus mainly on the four-or-more deck strategy we use in common six-deck games, while noting the strategies for fewer decks.

• 2-2: This is noted for four or more decks and for two decks if the dealer shows a 2 or 3, for two

decks vs. 2 or 3 if the dealer stands on soft 17, and for one deck vs. 2, but not 3. If you find yourself at a single-deck game, split 2s vs. 3 regardless of double after split rules.

Let's run some numbers on 2-2 vs. 2 and vs. 3, using the hand calculator at wizardofodds.com.

In the six-deck games that most of us play, strategies are the same regardless of whether the dealer hits soft 17, so let's assume a six-deck game in which the dealer hits soft 17.

If you're dealt 2-2 and the dealer's up card is a 2, then if you are allowed to double after splits, the average result of splitting the pair is a loss of 7.8 cents per $1 of your original wager, while the average loss is 11.3 cents if you hit.

If you can't double after splits, then the average loss remains at 11.3 cents if you hit, but zooms up to 15.4 cents if you double.

So the strategy tells you to split if you can double afterward, but hit if you can't.

Same deal on 2-2 vs. 3. The average loss if you hit is 8.0 cents, while it's lower at 6.6 cents and higher at 9.7 if you can't.

• 3-3: Basic strategy shows Ph vs. 2 and 3 regardless of number of decks or soft 17 rules. It also gets a Ph in single-deck games if the dealer shows a 7.

With 3-3 vs. 2, average loss when you hit is 13.9 cents, but a split brings a deficit drop to 12.9 cents per dollar of your first wager if you can double after splits. If you can't, splits increase the average loss to 20.6 cents.

If the dealer shows a 3, then the average loss when hitting 3-3 is 10.6 cents. If you split, you improve on that if you can double afterward, but increase your losses to 13.6 cents if you can't.

A pair of 2s is not a great start to a hand. The average result against a dealer's 2 or 3 is a loss regardless of what you do. Deciding whether to split is a matter of cutting losses rather than turning the hand intoa winner. Trimming losses is a worthy goal, and the option to double after split is one players like to see.

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