Never Split These Pairs

Never split tens, never split fives, and usually do not split fours. Two tens make a 20, an almost unbeatable hand you should keep intact. Two fives add up to 10, a strong doubling total best played as one hand, not two weak fives. Two fours make 8, which plays better as one hand than as two. Knowing which pairs to leave alone matters as much as knowing which to split, because a bad split throws good money after a weaker position.

Why should you never split a pair of tens?

A pair of tens is a made 20, and 20 is one of the best hands in blackjack. It beats every dealer total except 21 and ties another 20. When you split tens you give up that near certain winner in exchange for two hands that each start at ten and have to draw up from there. Most of those new hands will finish weaker than 20, and you have doubled your money at risk to get them. The temptation to split shows up most against a weak dealer card, where greed whispers that two strong starting hands could both win. The maths disagrees. Keeping your 20 wins far more over time than chasing two uncertain hands.

Why should you never split a pair of fives?

Two fives are not really a pair you want to think of as fives at all. Together they make 10, one of the best doubling and hitting totals in the game. Split them and you throw away that strong 10 to play two hands that each begin on a lonely five, which is one of the worst starting cards because it so often leads to a stiff total in the teens. Instead, treat your two fives as a hard 10. Against most dealer up-cards you double down on that 10, pressing your advantage. Against a dealer 10 or ace you simply hit. Under no sensible strategy do you split fives.

Why should you usually not split fours?

A pair of fours makes 8, a safe total that cannot bust on the next card. Split the fours and you create two hands each starting at four, forced to build up from a weak base. In most games you are better off hitting your 8 as a single hand. There is one narrow situation in games that allow doubling after a split, where splitting fours against a dealer 5 or 6 becomes marginally correct, because the dealer is very likely to bust and you can double the follow up. For most players in most games, though, the simplest and safest habit is to keep your 8 together and hit it.

What is the general logic behind not splitting?

Splitting is a tool for turning one mediocre hand into two hands that each have a better outlook, or for putting more money on the table when the dealer is weak and you hold a strong starting card. It backfires when your combined total is already good or when each individual card is weak on its own. Tens fail the test because your total is already excellent. Fives and fours fail it because the individual card is poor, so two hands starting from it are worse than one hand starting from the sum. The pattern to remember is simple:

• Do not split tens: keep the 20, it already wins most of the time.
• Do not split fives: play the 10, double it against weak dealer cards.
• Do not split fours in most games: hit the 8 instead.

Are there any pairs people wrongly think they should split?

Yes. Beyond tens, fives and fours, some players want to split face cards separately from numeric tens, believing a queen and a king are different from two plain tens. They are not: any two ten-value cards make 20, and you always keep it. Others split pairs of tens against a weak dealer to double their winnings, which is the single most common costly mistake at the table. And some split high pairs out of boredom or bravado. Discipline matters. The correct pairs to split, such as aces and eights, follow their own rules, but the never split group should be automatic refusals no matter how tempting the dealer up-card looks.

How much does avoiding a bad split save you?

Avoiding bad splits is part of basic strategy, the set of best plays that cuts the house edge to about half a percent. Splitting tens is especially expensive because you sacrifice a hand that wins the great majority of the time. Over many sessions, players who habitually split tens against weak dealer cards bleed a noticeable amount of expected value. Splitting fives is nearly as costly, because you trade a strong doubling 10 for two weak hands. None of these mistakes ruins a single session by itself, but the leak is steady, and plugging it costs nothing except the discipline to leave a good hand alone.

How do you build the habit of not splitting these pairs?

Treat tens, fives and fours as fixed rules you never reconsider at the table. Rehearse them until the answer is instant: tens stay a 20, fives become a 10 you usually double, fours become an 8 you hit. The danger moments are when the dealer shows a bust card and the split looks profitable, or when you are tired and reaching for a habit rather than the correct play. A strategy chart drilled in advance removes the second guessing. Knowing what not to split is half of pair strategy, and it protects the thin edge that correct basic strategy gives you before counting is ever involved.

Frequently asked questions

Should I ever split tens against a weak dealer card?

No. Splitting tens against a weak dealer card is the most common costly mistake in blackjack. Your two tens make 20, a hand that already wins the vast majority of the time. Breaking it into two hands that each start at ten gives up a near certain winner and doubles your money at risk for a worse expected result.

Why play two fives as a 10 instead of splitting them?

Because 10 is a strong doubling and hitting total, while a single five is one of the worst starting cards. Splitting fives forces you to build two hands from that weak base. Keeping them as a 10 lets you double against most dealer up-cards and press your advantage instead of scattering it.

Is it ever right to split fours?

Only in a narrow case. In games that allow doubling after a split, splitting fours against a dealer 5 or 6 is marginally correct because the dealer is very likely to bust. For most players in most games, the simpler and safer play is to keep your 8 together and hit it.

Do face cards count differently when deciding to split?

No. Any two ten-value cards, whether tens, jacks, queens or kings, make a 20, and you always keep that 20. A queen and a king are not worth splitting any more than two plain tens are. Treat every ten-value pair the same way and leave the strong 20 intact.