Northants are playing in division two after their fourth-placed finish in Group Three, and will be up against Surrey Essex, Durham, Gloucestershire and Glamorgan.
The County don't play Glamorgan as they met twice in the group stages, and it has been announced they will be hosting Surrey and Durham, and travelling to Gloucestershire and Essex.
David Ripley's men start with a trip to Bristol on Monday, August 30, before they face back-to-back home games.
First up is Surrey on Sunday, September 5, with Durham coming to the County Ground a week later (Sept 12).
Northants will then wrap up their summer of cricket with a trip to reigning county champions Essex on Tuesday, September 21.
Having failed to qualify for division one and the chance to play for the County Championship title, the teams are playing to see who finishes between seventh and 12th in the final table, with all of the counties carrying over points from the Group stage.
Each team takes half of the total points they accrued from the matches against the team they qualified with.
So in Northants' case they begin the divisional stage with 16 points as they collected 32 points from their win and draw against Glamorgan.
That means they start in second place in Division Two, with Essex (19) on top.
Following them are Surrey (13), Gloucestershire (12), Glamorgan (11.5) and Durham (4).
As it stands, following the lifting of Government Covid-19 restrictions, season ticket holders and life members of Northants no longer need to claim tickets in advance for the two home matches, and seats are not allocated.