Looking down from the ridge of Bourton Hill to where the Cherwell lay glinting in the sun-filled meadows, Waller had a perfect view of the king's army. The forces were evenly balanced both around 9,000 men, but the King had allowed his men to become dangerously strung out along the river. Ahead was Cropredy Bridge and about a mile to South of that lay the river crossing at Slat Mill Ford. Between the two lay the King's straggling rearguard. Despatching Lieutenant-General John Middleton to cross Cropredy Bridge with two regiments of horse and nine companies of foot, Waller himself took 1,000 men across Slat mill Ford hoping to catch the Royalist rear in a pincer movement.
Although Cropredy Bridge was held by a party of the king's dragoons, they were readily beat off by Middleton. Unfortunately, his cavalry then proceeded to repeat the original mistake of the Royalists. Racing ahead of their infantry, they too speedily pursed the enemy having no foot within half a mile.
As Middleton's dragoons collided with the main body of the Royalist force, the King became alerted to the perilous situation in which he had left his rearguard. He was fortunate in having two highly capable commanders at the tail of his army. At Slat Mill, the young Earl of Northampton, still in his teens, reacted with a swift charge, which drove Waller's force back across the Cherwell. Meanwhile at Cropredy Bridge the Earl of Cleveland having watched the Parliamentarian cavalry disappear into the haze, seized the opportunity to attack their unsupported infantry. Middleton's foot, thinking that the devil had come upon them in a cloud of dust, beat a hasty retreat back to the bridge.
Although Waller had lost the initiative, the King was unwilling to risk forcing a passage over the Cherwell and the affray ended in a stalemate. Eventually, receiving intelligence of Parliamentarians nearby, the Royalist slipped away under cover of darkness. While they had suffered few casualties, Waller had lost 700 men including many deserters.