The Addicks stand just two points above the relegation zone, but three points at the The Valley will put them beyond the reach of Millwall and Doncaster Rovers below them.
Meanwhile, their opponents Watford are safely in mid-table and were beaten 4-2 by Derby County on Saturday.
They have lost their last two league matches and have won just four games away from Vicarage Road this season.
Both teams will come into the match with strikers in good form, as Marvin Sordell has scored four times for Charlton in his last two outings, while Troy Deeney netted his 23rd league goal of the season at Pride Park.
Possible starting lineups
Charlton: Hamer, Solly, Fox, Dervite, Morrison, Cousins, Poyet, Ajdarevic, Jackson, Harriott, Sordell
Watford: Doyley, Cassetti, Ekstrand, Riera, McGugan, Tozser, Battocchio, Pudil, Deeney, Ranegie
Sports Mole says: 2-1