A West Ham United XI boasting a strike force of Frederic Piquionne and Sam Baldock provided the opposition for the Cobblers, who lined up in their all new fluorescent green away strip, for their final home pre-season friendly.
Lee Nicholls, signed on loan from Wigan Athletic started in goal for the Cobblers.
Northampton's scorers were Clive Platt on 10 minutes followed by Kelvin Langmead at 66 with the third from Alex Nicholls at 82 minutes.
The attendance was 1414.