Coventry City will face trips to Rotherham United and Port Vale FC next season.
The Millers beat Aldershot Town 2-0 to earn promotion to League One and send Aldershot to the Conference along with Barnet who lost 2-0 at Northampton Town.
Micky Adams Port Vale side drew 1-1 at Wycombe Wanderers to ensure they went up in third place.
The final team to join Champions Gillingham will be decided from the Play-Offs which start this week with Bradford City V Burton Albion and , Northampton Town V Cheltenham Town.