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.
More top news
The Duke and Duchess of Cambridge and Prince Harry are to attend a private service in to re-dedicate the grave of Diana, Princess of Wales.
England batsman Alastair Cook has broken the Essex county batting record scoring 373 with partner Nick Browne against Middlesex.
There are calls for safety improvements on a road linking Peterborough to Northamptonshire, where four have died in the past two months.