The 19-year-old, who has made four senior appearances for the Shrimpers, has committed himself to Roots Hall until the summer of 2018.
"I'm pleased to extend my time here. I've really enjoyed it here and the club have looked after me since day one," he told the club's official website.
Smith joined Southend on schoolboy terms in 2008.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Forest Green RoversForest Green | 18 | 12 | 4 | 2 | 35 | 14 | 21 | 40 |
| 2 | York City | 18 | 11 | 5 | 2 | 33 | 14 | 19 | 38 |
| 3 | Barnet | 18 | 12 | 1 | 5 | 38 | 23 | 15 | 37 |
| 4 | Oldham AthleticOldham | 18 | 9 | 7 | 2 | 29 | 17 | 12 | 34 |
| 5 | Gateshead | 18 | 10 | 4 | 4 | 30 | 24 | 6 | 34 |
| 6 | Rochdale | 18 | 9 | 3 | 6 | 27 | 18 | 9 | 30 |
| 7 | Halifax TownHalifax | 18 | 8 | 5 | 5 | 20 | 16 | 4 | 29 |
| 8 | Yeovil TownYeovil | 18 | 8 | 4 | 6 | 21 | 16 | 5 | 28 |
| 9 | Solihull MoorsSolihull | 18 | 8 | 4 | 6 | 32 | 28 | 4 | 28 |
| 10 | AltrinchamAltrincham | 18 | 7 | 6 | 5 | 28 | 23 | 5 | 27 |
| 11 | Sutton UnitedSutton | 18 | 7 | 4 | 7 | 26 | 26 | 0 | 25 |
| 12 | Eastleigh | 18 | 6 | 6 | 6 | 25 | 25 | 0 | 24 |
| 13 | Dagenham & RedbridgeDag & Red | 18 | 5 | 7 | 6 | 30 | 22 | 8 | 22 |
| 14 | Hartlepool UnitedHartlepool | 18 | 5 | 7 | 6 | 18 | 21 | -3 | 22 |
| 15 | Tamworth | 18 | 6 | 4 | 8 | 20 | 32 | -12 | 22 |
| 16 | Southend UnitedSouthend | 18 | 5 | 6 | 7 | 20 | 22 | -2 | 21 |
| 17 | Woking | 18 | 5 | 5 | 8 | 19 | 24 | -5 | 20 |
| 18 | Aldershot TownAldershot | 18 | 4 | 7 | 7 | 23 | 29 | -6 | 19 |
| 19 | Braintree TownBraintree | 18 | 5 | 4 | 9 | 14 | 20 | -6 | 19 |
| 20 | WealdstoneWealdstone | 18 | 4 | 6 | 8 | 18 | 25 | -7 | 18 |
| 21 | Fylde | 18 | 5 | 3 | 10 | 23 | 37 | -14 | 18 |
| 22 | Maidenhead UnitedMaidenhead | 18 | 4 | 4 | 10 | 21 | 31 | -10 | 16 |
| 23 | Boston UnitedBoston | 18 | 2 | 5 | 11 | 16 | 31 | -15 | 11 |
| 24 | Ebbsfleet | 18 | 1 | 5 | 12 | 15 | 43 | -28 | 8 |
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