Conor Washington's second-half brace was enough to claim all three points, with Alex Jones coming off the bench to score a consolation on his Town debut. Here are our player ratings...
9. Tariqe Fosu
His first start in six weeks and it came against his former club. Delivered a fine cross that would have been perfect for McGeehan to convert without McIntyre's illegal intervention. But then missed Town's best opening at 1-1. Wasn't an easy chance but he should have done better... 7 Photo: Pete Norton
10. Tyler Roberts
There were moments where he looked as good as anyone on the pitch. His delightful curled cross was so nearly on a plate for Fosu. But he couldn't sustain that quality for long enough, especially when Cobblers needed to make more of their good spells, to properly damage Charlton... 7 Photo: Pete Norton
11. Dara Costelloe
Fantastic display up front. Constantly on the move, running from side to side and through the middle, making life difficult for Charlton's defenders. Demanded the ball for the penalty and justified his confidence with a well-taken spot-kick. Up to four for the season. Nearly set up a stoppage-time leveller for Wilson... 8 CHRON STAR MAN Photo: Pete Norton
12. Max Dyche
Lost out in the air when Aneke's flick on sent Godden through for the winner... 6 Photo: Pete Norton