The Scottish army suffered a dramatic defeat, but the contemporary claims of 10,000 or more killed have to be dismissed, though it seems fairly certain that the Scots lost far more killed and wounded than did the English. The battlefield was however said to have been thickly covered with bodies which ‘were left unburied, and were eaten by the birds of the air and the beasts of the field.’ There were also significant numbers captured, with supposedly some 50 Scottish knights taken prisoner and, in usual fashion for the period, held to ransom.

However many Scots were actually killed, the numbers of Scottish losses would have been much greater had the English forces staged a significant pursuit. They apparently did not and it has been suggested that this was primarily because the majority of the English cavalry had dismounted to fight and cavalry was certainly the most important force in any pursuit. Though it should always be borne in mind that the dangers of exploiting what turned out to be a feigned enemy retreat were well known, not least from the fate of the Saxon army at Hastings.

Northallerton was a dramatic defeat for the Scots, but the English failed to capitalise upon it, at least in military terms. Soon after the battle the English levies were disbanded and only a small force was retained to reduce the castle at Malton, which was held by supporters of Matilda. There was no major offensive to drive the Scots out of the northern territories. By early in September David had rallied some 14,000 troops in Carlisle to meet any English counter attack, but none was launched because of the continuing rebellion in the south.