Contostavlos, of St Albans, Hertfordshire, stood in the dock in a white shirt, black trousers and black trainers as the charge was read to him.
He was granted unconditional bail and will stand trial at Chelmsford Magistrates' Court on June 18.
The former N-Dubz singer finished in second place on reality show Celebrity Big Brother in January.
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Becoming drier by this evening with the chance of a late sunny spell.
The Chief Executive of Southend United has told ITV News Anglia that his players deserved to win promotion to League One at Wembley.
Some sunny intervals are possible initially this morning but cloud and patchy rain will gradually sweep in as the day goes on.