When to Keep vs. Discard 5s in Cribbage: Complete Analysis

Q: "Should I ever throw a 5 to my opponent's crib?"

"Rarely. A 5 in your opponent's crib adds an average of 3.1 points because it pairs with all 16 ten-value cards to make fifteens. Only throw a 5 if keeping it requires sacrificing an exceptional hand (e.g., you'd otherwise keep a 12-point hand with the 5 gone) or if you would otherwise have to throw both 5s together to opponent — which is far worse."

Q: "How much is a 5 worth in cribbage?"

"A single 5 has the highest 'starter potential' of any rank. It makes a fifteen with any of the 16 ten-value cards (10, J, Q, K) — roughly 31% of the remaining deck. With a random starter, holding a single 5 with otherwise weak cards adds approximately 2.4 expected points. Paired with other ten-cards already in hand, the 5 scores immediately without needing the cut."

Q: "Should I keep 5-5 or break up the pair?"

"Almost always keep 5-5. The pair is 2 guaranteed points, and any ten-card starter adds 4 more (two fifteens), giving an expected value around 6.5 points from the pair alone. To your own crib, 5-5 averages 5.7 points. Only break 5-5 apart if the alternative keep produces 4+ more expected points — which is rare."

Q: "What's the best card to pair with a 5 in your hand?"

"Ten-value cards (10, J, Q, K) are the ideal companion — each makes an immediate fifteen (2 pts). A 5 with three ten-cards scores 6 points before any cut. Second best: another 5 (pair + double fifteen potential). Third: cards forming runs (4-6 for a 4-5-6 run opportunity)."

Q: "When IS it right to throw a 5 to opponent?"

"When the alternative is clearly worse: throwing 5-10 or 5-J (instant fifteen) would be more damaging than a lone 5. Also justified when keeping the 5 forces you to break a guaranteed high-value hand. If you must throw a 5, minimize damage by pairing it with a 5-A or 5-2 — wide-spread low cards with no synergy for fifteens."

Q: "Should I lead a 5 during the pegging phase?"

"No — leading a 5 is one of the most dangerous pegging mistakes. Any ten-value card played by opponent immediately scores 15-2. Lead a low card (A, 2, 3, or 4) instead. Save your 5 to respond to an opponent's ten-card lead, scoring the fifteen yourself."

Q: "What about 5s in 3-player cribbage?"

"In 3-player cribbage the crib is shared between all players, making 5s slightly less dangerous to discard since the crib benefits are split. However, since each player discards only 1 card to the crib, your 5 will be there with three other unknown cards — still significant risk. Apply the same principle: keep 5s unless forced."

Master the most important discard decision in cribbage — when to keep your 5s and when to throw them. Includes expected value tables, pegging traps, and scenario analysis.

Updated: April 23, 2026 · 7 min read

By Garrett Pegg · Reviewed against ACC standards

When to Keep vs. Discard 5s in Cribbage

The short answer: Keep your 5s. A 5 makes a fifteen with 16 out of the remaining 51 cards (31.4%), making it the most fifteen-fertile card in the deck — and therefore the most dangerous card to put in an opponent’s crib.

Mastering 5 decisions is the single highest-leverage discard skill in cribbage.

Why 5s Are Special

The Probability

A 5 makes fifteen with every ten-value card:

Card	Quantity	Notes
10	4
Jack	4	Also scores nobs if matching suit
Queen	4
King	4
Total	16	31.4% of remaining deck

No other rank comes close. A 6 only pairs for fifteens with 9s (4 cards, 7.8%). A 7 only pairs with 8s (4 cards). The 5 outperforms them all by a factor of 4.

Expected Value

Situation	Expected Value Added
Single 5, three random cards, random starter	+2.4 pts
Single 5 + one ten-card already in hand	+4.0 pts (instant 15 + cut potential)
Single 5 + two ten-cards in hand	+6.0 pts (two instant 15s + cut potential)
5-5 in hand, random starter	+6.5 pts average
5-5 in YOUR crib	5.7 pts average
Single 5 in OPPONENT’S crib	−3.1 pts (cost to you)

The Golden Rule

Never throw a 5 to your opponent’s crib unless forced.

This is cribbage’s most important strategic principle. A single 5 in an opponent’s crib adds an average of 3.1 points to their score — because 16 of the remaining 51 cards make it a fifteen, and the starter card compounds the damage further.

Scenario Analysis

Situation 1: You’re Dealt One 5

Hand: A-4-5-7-J-K (You’re pone - opponent’s crib)

Keep	Hand Value	Throw	Crib Damage	Net
A-4-5-7	4	J-K	Low	Good
4-5-7-J	7	A-K	Low	Better
5-7-J-K	6	A-4	Low	Good
4-7-J-K	4	A-5	5 danger!	Avoid

Decision: Keep the 5. Throw A-K or A-4 (wide cards, low risk).

Situation 2: You’re Dealt 5-5

Hand: 3-5-5-8-9-Q (You’re dealer - your crib)

Keep	Hand Value	Throw	Crib Value	Total EV
5-5-8-9	6	3-Q	~3	~9
3-5-5-9	4	8-Q	~2	~6
5-5-9-Q	8	3-8	~2	~10

Decision: Keep 5-5-9-Q. Send 3-8 (or 5-5 to crib if hand was stronger).

Wait, should 5-5 go to YOUR crib?

Yes, sometimes! 5-5 to your own crib averages 5-6 points because:

Guaranteed pair (2 pts)
Two ways to make fifteen with any ten-card (likely +4)
Possibility of 5 as starter (+6 more)

Only send 5-5 to your crib if your remaining hand is still strong.

Situation 3: You’re Dealt 5-10/5-J/5-Q/5-K

Hand: 2-5-7-10-J-K (You’re pone)

This is painful. You have a 5 but easy fifteen companions.

Keep	Hand	Throw	Crib Damage
5-10-J-K	14	2-7	Low
2-5-7-10	4	J-K	Low
5-7-10-J	10	2-K	Low

Decision: Keep 5-10-J-K for 14 guaranteed points. Yes, throwing 2-7 is fine to opponent.

The 5 is worth keeping BECAUSE you have the ten-cards.

Situation 4: Must You Throw the 5?

Hand: 5-6-7-8-9-10 (You’re pone)

Amazing run potential, but you have a 5.

Keep	Hand	Throw	Analysis
6-7-8-9	8	5-10	5-10 = instant 15 to opponent!
5-6-7-8	7	9-10	Safe throw
6-7-8-10	6	5-9	5 to opponent, but no instant 15

Decision: Keep 5-6-7-8 and throw 9-10. Avoid gifting fifteens.

Crib Analysis: 5 to Your Own Crib

When you’re dealer, 5s in YOUR crib are excellent.

Throw	Expected Crib Points	Notes
5-5	5.5+	Pair guaranteed, fifteen likely
5-J	4.5+	Instant fifteen, nobs chance
5-10/Q/K	4+	Instant fifteen
5-A	3+	5 has potential, A is weak
5-9	3.5	No instant combo but solid

What If You MUST Throw a 5 to Opponent?

Sometimes you’re forced. Pair it with the least damaging card:

Throw	Damage Level	Why
5-A	Low	A makes nothing easily
5-2	Low	2 makes nothing easily
5-9	Medium	9-6 is a fifteen, but unlikely
5-10/J/Q/K	Very High	Instant fifteen!
5-5	Devastating	Pair + multiple fifteen potential
5-6	Bad	Close cards can run

Best forced throw: 5-A or 5-2

5s During the Pegging Phase

The 5’s fifteen potential doesn’t stop at the discard — it creates traps and opportunities throughout the pegging phase too.

Never Lead a 5

Leading a 5 is one of the most common pegging mistakes. Any ten-value card played by your opponent immediately scores 15-2, handing them a free gift. Since roughly 31% of cards are ten-value, you’re giving away points nearly a third of the time.

Lead low instead: A, 2, 3, or 4 are safe pegging leads. They can’t form fifteens without multiple cards, giving you time to respond.

Exploit Opponent’s Ten-Card Lead

When your opponent leads a 10, J, Q, or K, play your 5 immediately for 15-2. This is the strongest peg response to a ten-card lead — you score 2 points and put the running count at 15.

The 5-5 Pegging Trap

If you hold 5-5 and opponent leads a 5, pair it for 2 points. But beware: opponent may hold the fourth 5, giving them a pair-royal (6 pts). Unless you’re confident they don’t hold the fourth 5 (e.g., you’ve seen other 5s played), be cautious.

Count Awareness at 15 and 31

The running count at 10 is a trap for anyone holding a 5 — they’ll be tempted to score 15. Use this: if you’re playing aggressively and opponent is at 10, playing a non-5 card may bait them into a predictable response you can exploit.

At a count of 26 (near 31), a 5 finishes at exactly 31 for 2 bonus points. Holding a 5 with a count that approaches 26 gives you strong closing options.

Board Position Considerations

Your board position affects how strictly you apply the 5 rules.

When far behind (opponent near 100, you near 80): Consider breaking the golden rule. Keeping a weak hand to avoid gifting a 5 may cost you the game. A desperate keep of points matters more than crib damage control when you’re chasing.

When near the stinkhole (115–120 pts): Every point counts in both directions. A 3-point gift to an opponent’s crib at this stage is potentially game-ending. The golden rule becomes even more important in the endgame.

When comfortably ahead: Play conservatively. Keep your 5s, limit opponent’s crib, and grind out the win. Defensive pegging (avoiding letting opponent score) pairs naturally with holding your 5s.

See end-game strategy for how board position changes all your decisions late in the game.

The 5-5-5 Dream

If dealt three 5s:

Hand: 5-5-5-X-Y-Z

Keep all three 5s unless X-Y-Z is extraordinary. Why?

6 points from pairs
Any ten-card cut = +8 (four more fifteens)
5 cut = 29-hand potential!

Practice Problems

Hand 1: 2-5-5-6-6-K (Dealer)

Keep: 5-5-6-6 (16 pts) or 2-5-6-6 + send 5-K?
Answer: Keep 5-5-6-6 (already 16, excellent cut potential)

Hand 2: 4-5-6-7-9-J (Pone)

Keep: 4-5-6-7 (12 pts run + fifteens) or 5-6-7-9?
Answer: Keep 4-5-6-7. Send 9-J (wide, not dangerous)

Hand 3: A-3-5-7-9-K (Pone)

Tough hand. Keep 5 with what?
Answer: Keep A-3-5-7 (no scoring but 5 has potential), throw 9-K

Key Takeaways

5s make fifteens with 31.4% of the deck — 16 out of 51 remaining cards
Never gift a 5 to opponent’s crib — it adds an average 3.1 points to their score
5-5 to your own crib averages 5.7 points — one of the best crib discards possible
Never lead a 5 in pegging — any ten-card response scores 15-2 for opponent
Exploit ten-card leads — respond with your 5 to score the fifteen yourself
Best forced throw: 5-A or 5-2 (widest spread, least crib synergy)
Board position matters — the golden rule applies most strictly in the endgame

For the complete framework of all discard decisions, see the Discard Strategy guide. To apply 5-awareness during the play phase, see Pegging Strategy.

Ready to apply the 5-rule in a live hand? Play a free game and watch for 5s on every deal.

📚 Full Discard Strategy

Frequently Asked Questions

Should I ever throw a 5 to my opponent's crib?

Rarely. A 5 in your opponent’s crib adds an average of 3.1 points because it pairs with all 16 ten-value cards to make fifteens. Only throw a 5 if keeping it requires sacrificing an exceptional hand (e.g., you’d otherwise keep a 12-point hand with the 5 gone) or if you would otherwise have to throw both 5s together to opponent — which is far worse.

How much is a 5 worth in cribbage?

A single 5 has the highest ‘starter potential’ of any rank. It makes a fifteen with any of the 16 ten-value cards (10, J, Q, K) — roughly 31% of the remaining deck. With a random starter, holding a single 5 with otherwise weak cards adds approximately 2.4 expected points. Paired with other ten-cards already in hand, the 5 scores immediately without needing the cut.

Should I keep 5-5 or break up the pair?

Almost always keep 5-5. The pair is 2 guaranteed points, and any ten-card starter adds 4 more (two fifteens), giving an expected value around 6.5 points from the pair alone. To your own crib, 5-5 averages 5.7 points. Only break 5-5 apart if the alternative keep produces 4+ more expected points — which is rare.

What's the best card to pair with a 5 in your hand?

Ten-value cards (10, J, Q, K) are the ideal companion — each makes an immediate fifteen (2 pts). A 5 with three ten-cards scores 6 points before any cut. Second best: another 5 (pair + double fifteen potential). Third: cards forming runs (4-6 for a 4-5-6 run opportunity).

When IS it right to throw a 5 to opponent?

When the alternative is clearly worse: throwing 5-10 or 5-J (instant fifteen) would be more damaging than a lone 5. Also justified when keeping the 5 forces you to break a guaranteed high-value hand. If you must throw a 5, minimize damage by pairing it with a 5-A or 5-2 — wide-spread low cards with no synergy for fifteens.

Should I lead a 5 during the pegging phase?

No — leading a 5 is one of the most dangerous pegging mistakes. Any ten-value card played by opponent immediately scores 15-2. Lead a low card (A, 2, 3, or 4) instead. Save your 5 to respond to an opponent’s ten-card lead, scoring the fifteen yourself.

What about 5s in 3-player cribbage?

In 3-player cribbage the crib is shared between all players, making 5s slightly less dangerous to discard since the crib benefits are split. However, since each player discards only 1 card to the crib, your 5 will be there with three other unknown cards — still significant risk. Apply the same principle: keep 5s unless forced.