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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There'll be a few showers about on Saturday but it will slowly brighten up and Sunday should be mostly dry. It will stay cool in the wind.