The 23-year-old left the Millers at the end of last season after having his contract terminated by mutual consent.
Newton, who started his career at Newcastle United, made 14 appearances for the Championship club during the 2014-15 campaign.
Cambridge start the new League Two season at home to Newport County on August 8.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Wycombe WanderersWycombe | 19 | 13 | 4 | 2 | 43 | 22 | 21 | 43 |
| 2 | Birmingham CityBirmingham | 18 | 13 | 3 | 2 | 34 | 16 | 18 | 42 |
| 3 | Wrexham | 20 | 12 | 5 | 3 | 30 | 13 | 17 | 41 |
| 4 | Huddersfield TownHuddersfield | 19 | 11 | 3 | 5 | 30 | 18 | 12 | 36 |
| 5 | Stockport CountyStockport | 20 | 9 | 6 | 5 | 32 | 21 | 11 | 33 |
| 6 | Reading | 19 | 9 | 4 | 6 | 30 | 28 | 2 | 31 |
| 7 | Barnsley | 20 | 8 | 6 | 6 | 29 | 26 | 3 | 30 |
| 8 | Bolton WanderersBolton | 18 | 9 | 3 | 6 | 28 | 29 | -1 | 30 |
| 9 | Lincoln CityLincoln | 20 | 7 | 7 | 6 | 26 | 25 | 1 | 28 |
| 10 | Blackpool | 19 | 7 | 5 | 7 | 29 | 31 | -2 | 26 |
| 11 | Mansfield TownMansfield | 18 | 7 | 4 | 7 | 22 | 22 | 0 | 25 |
| 12 | Stevenage | 18 | 7 | 4 | 7 | 15 | 17 | -2 | 25 |
| 13 | Peterborough UnitedPeterborough | 19 | 7 | 3 | 9 | 37 | 35 | 2 | 24 |
| 14 | Charlton AthleticCharlton | 19 | 6 | 6 | 7 | 18 | 19 | -1 | 24 |
| 15 | Exeter CityExeter | 19 | 7 | 3 | 9 | 17 | 21 | -4 | 24 |
| 16 | Wigan AthleticWigan | 19 | 6 | 5 | 8 | 17 | 16 | 1 | 23 |
| 17 | Rotherham UnitedRotherham | 18 | 6 | 5 | 7 | 19 | 20 | -1 | 23 |
| 18 | Leyton Orient | 19 | 6 | 4 | 9 | 19 | 20 | -1 | 22 |
| 19 | Northampton TownNorthampton | 20 | 5 | 6 | 9 | 21 | 29 | -8 | 21 |
| 20 | Bristol Rovers | 19 | 6 | 3 | 10 | 17 | 28 | -11 | 21 |
| 21 | Crawley TownCrawley | 19 | 5 | 4 | 10 | 20 | 32 | -12 | 19 |
| 22 | Cambridge UnitedCambridge | 19 | 4 | 5 | 10 | 20 | 31 | -11 | 17 |
| 23 | Burton Albion | 19 | 2 | 6 | 11 | 16 | 30 | -14 | 12 |
| 24 | Shrewsbury TownShrewsbury | 19 | 3 | 2 | 14 | 19 | 39 | -20 | 11 |
| > League One Full Table | |||||||||
