Aribim Pepple and Adam Crowther were on target as Southend claimed a 2-0 victory at Halifax in the Vanarama National League.
Billy Waters should have put the West Yorkshire side ahead when he met a Jamie Cooke cross after 27th minutes, but missed the target.
Pepple made the hosts pay 10 minutes before interval as he beat a couple of challenges to fire past Sam Johnson.
Crowther made certain of a Shrimpers victory just after the hour when he adjusted well to head home from a James Morton corner.
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