What order do the cards need to be in to count as a run during cribbage pegging? I get asked this question a lot. So let's clear this up shall we?
First, runs do not need to be in numerical order. 2-3-4 is a run but so is 2-4-3.
To count as a run while pegging, there must be at least three (3) cards played. Also, runs of three or more must be played before 31 is reached. Runs count as one point for every card in the run. So a run of three cards is three points, a run of four cards is four points, etc. Aces are always low, so Q-K-A is not a run. There are no double runs when pegging. 3-4-4-5 counts as a double run in a hand, but not when pegging. The pair breaks the sequence.
Again, runs do not need to be in numerical order. If you can arrange the last three or more cards played in numerical order (without a break) it constitutes a run. However, a pegging reset by a player getting 31 or a "Go" cancels the run sequence.
Is 3-4-2 a run? Yes. 2-3-4.
Is 3-5-2-4 be a run? Yes. 2-3-4-5.
Is 6-7-8-5 rearrangeable? You bet. 5-6-7-8.
It should be noted that runs that equal 15 or 31 get points in the run plus the two points. So a run of 4-5-6 gets three points for the run and two points for fifteen - 5 points total. Along those lines, a player who scores a run with the last card played gets points in the run plus last card (1 point).
Runs don't always begin with a player getting 3 points. Let's say the pegging order is as follows: 2-5-4-Ace. No pegging points right? Right! But if someone plays a 3 next it's a five card run for 5 points.