The Rule of Eleven is used by the Defender to determine the number of high cards in Declarer's hand in the suit led by partner. It can only be used when partner's  opening lead is the fourth card down from the top of the suit led. Note: the lead could also be in the middle of the play, but it must be the first time that the particular suit has been played.
 It is important to see the card your partner plays on the first trick.
      THE RULE: Subtract the value of the card led by partner from eleven (11). The calculated answer tells you the total number of cards higher than the card led that are in Dummy, your hand and Declarer's hand. Example: If partner leads the 5, then there are 11 - 5 = 6 cards higher than the 5. And these 6 cards are in the Dummy, your hand and in Declarer's hand. Then, by looking at Dummy and y our hand, you can figure out the number of high cards (in the suit led) in Declarer's hand.



Q 8 5


K 9 7

EXAMPLE 1. (above) Your partner leads the 4. Using the Rule of Eleven: 11 - 4 = 7; there are seven (7) cards higher than the 4 between the Dummy, your hand and the Declarer's hand. Looking at the Dummy and at your hand you see six cards higher than the 4. Q 8 5 in Dummy and K 9 7 in your hand. Therefore Declarer has only one care higher than the 4. Let's assume Declarer plays the 5 from Dummy. If you put up your King and Declarer's high card is the Ace, then Declarer will win the trick and the Queen in Dummy will be a winner. So play the 7 and let Declarer win only one trick in the suit.



Q 9 8 



K 10 4

EXAMPLE 2. (above) Your partner leads the 6. Using the Rule of Eleven: 11 - 6 = 5, there are 5 cards higher than the 6 between Dummy, your hand and the Declarer's hand. Looking at the Dummy and at your hand you see all five (Q 9 8 and K 10 4). So Declarer does not have a card higher than the 6. So if Declarer plays the 9 or 8 from Dummy, win the trick with the 10, then play the King, and then the 4 to your partner's Ace. If you played the King on the first trick, Dummy's Queen would be a winner.
      Note: The Rule of Eleven can also be used in suit contracts.

For the curious and/or mathematically inclined, this is why the Rule of Eleven works.

               spot number                 honors
       2  3  4  5  6  7  8  9       10   J    Q     K      A 

       2  3  4  5  6  7  8  9   10  11  12   13   14 
                       numerical value

Partner leads Fourth Best. Subtract the Spot Number of the card from fourteen (14) to find how many cards are higher than that card.  e.g. if  partner leads the S 5  then there are nine (9) cards higher than the S 5 (14 - 5 = 9). But three of  these higher cards are in partner's hand.  Why? Because partner led Fourth Best (see FOURTH BEST). Subtracting 3 from 9 
(9 - 3 = 6) we get six (6). So there is a total of 6 cards higher than partners opening lead of the S 5. Where are they? The 6 higher cards are distributed among the Dummy, your hand and Declarer’s hand.  But instead of subtracting the spot number of the card from 14 then again by 3, just subtract once from ELEVEN (11 - 5 = 6). Hence RULE OF ELEVEN.