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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Any early rain should clear, leaving a dry morning. Some brighter spells could develop and it will be feeling very mild. Highs of 16 deg C.
Teams searching for the missing RAF serviceman Corrie McKeague have admitted they're running out of logical places to look for him.
Cloud will thicken this evening but most places will remain dry. However some rain will creep in early Monday morning. Lows of 8 deg C.