On a wretched, wet afternoon in Berkshire, the Addicks showed bucket loads of resolve to record their second away win of the season.
Chris Solly returned to the starting line-up and Morgan Fox, as expected, came in for the injured Rhoys Wiggins.
Igor Vetokele started in place of George Tucudean, who dropped to the bench, where he was joined by the returning duo of Joe Gomez and Frederic Bulot.
Callum Harriott kept his place and partnered Vetokele at the front.
The decisive goal came six minutes before the break. Chris Solly completely mastered Reading left-winger, Jordan Obita, giving him opportunities to move forward.
He delivered a left-footed cross from the right which picked out Vetokele. The Angolan hitman directed his header past Adam Federici’s right hand to give his team the lead.
Reading had the majority of possession after the break as they pressed for the equaliser but the Charlton rearguard held firm. The Royals best chances came when Oliver Norwood hit the outside of the post and Stephen Henderson had to make a smart save to foil Jamie Mackie.
The best chance of the half though, went to the visitors six minutes from time. Johann Gudmaundsson broke down the left and played a perfect ball into substitute, George Tucudean.
The Romanian was unmarked with only Federici to beat, but hit the ball straight at the keeper. The rebound fell kindly for Tucudean but his second effort was blocked.
There was a collective sharp intake of breath in the away end when the fourth official indicated there would an incredible six minutes of added time to be played.
Bob Peeters’ side saw it out without mishap to take the three points though.
Charlton: Henderson, Solly, Ben Haim, Bikey,Fox; Gudmundsson (Bulot 88), Buyens, Jackson, Cousins; Harriott (Tucudean 81), Vetokele (Coquelin 64).
Subs (not used): Pope, Wilson, Gomez, Onyewu.
Goal: Vetokele 39.
Bookings: Gudmundsson 87 (foul) Jackson 90(foul).
Reading: Federici; Kelly (Blackman 80) , Gunter, Pearce, Hector; Mackie, Norwood, Williams, Obita; Cox (Robson-Kanu 77), Murray.
Subs (not used): Andersen, Cooper, Akpan, Taylor.
Booking: Cox 73 (foul).
Referee: Neil Swarbrick (Lancashire).
Attn: 16,989 (1,449 Charlton).