The victorious British did not press the defeated Americans. They settled down to a repast of “some cold pork and grogg.” Washington's troops fled to Chester, where they were swiftly reorganized. The Americans were beaten but unbowed. A captain in one of Washington's Continental regiments later wrote, “I saw not a despairing look, nor did I hear a despairing word. We had solacing words always ready for each other — ‘Come, boys, we shall do better another time.' — Had a man suggested, or merely hinted the idea of giving up, — he would have been knocked down, and if killed, it would have been no murder.”

Lafayette was quite pleased with himself. He had ridden into the thick of the fighting, trying to rally the collapsing right wing, and had been wounded in the process. He wrote his wife the next day, “messieurs les anglais … wounded me slightly in the leg, but it is nothing … for the ball did not touch bone or nerve.”

Washington shared his men's resilience. He notified Congress of the defeat, which called on the neighboring states to send reinforcements. Within three weeks, Washington's army was larger than it had been before the battle. Washington kept his army between Philadelphia and the slowmoving British. He camped near White Horse Tavern, twenty miles west of the city. Infantry under Generals William Maxwell and Anthony Wayne and cavalry under Casimir Pulaski skirmished with the British.

Washington wanted to fight again. On September 16, he drew his army up in line of battle. Howe did the same. Then nature interposed itself; a violent rainstorm turned the prospective battlefield into a quagmire. A Hessian officer wrote that he and his men sank in mud up to their calves. The muskets on both sides were wetted too thoroughly to be fired. Disastrously for the Americans, the downpour soaked 400,000 of their cartridges because of defective cartridge boxes. Henry Knox wrote it was “a most terrible stroke to us.” Washington had no choice but to withdraw until he could get his ammunition replenished. He left behind a division of 1,500 men under Anthony Wayne to threaten Howe's rear. Loyalists gave away the location of Wayne's camp. On the evening of September 20, a British force under Major General Charles Grey surprised the Americans with a bayonet attack and routed them, inflicting heavy losses.

The dispersal of Wayne's column freed Howe for the war of maneuver at which he excelled. He feinted toward the northwest and Washington's base of supply. When Washington moved to cover this advance, Howe suddenly veered back toward the now open road to Philadelphia. The Americans found themselves too far away to stop the British. Washington encamped and gave his men four days of rest. Congress left Philadelphia for Lancaster, Pennsylvania. Once again it granted Washington special powers for sixty days, especially in the area of procurement. Washington desperately needed blankets and extra clothing for his men, many of whom had lost their bedrolls at Brandywine Creek. There was not much to be had in the disorder occasioned by the British advance.

Howe's army entered Philadelphia on September 26. Loyalists enthusiastically welcomed him. A Patriot witness recorded that Howe's troops were received “amidst the acclamation of some thousands of the inhabitants, mostly women and children.” Howe and his officers became the center of a lively social scene. Loyalist Philadelphia proved to be transient restoration; too few loyalists turned out to fight. When the British army left the following year, Howe's loyalist establishment would have to leave with it.