Tulisa Contostavlos has denied being concerned with the supply of Class A drugs at Westminster Magistrates Court.
The 25-year-old arrived at Westminster Magistrates Court in central London on Thursday morning, looking defiant.
The N-Dubz star, of Friern Barnet, north London, is accused of setting up an £860 deal for 13.9 grams of cocaine to an undercover reporter.
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She appeared alongside rapper Mike GLC, also known as Michael Coombs, 35, of Velocity Way, Enfield, north London, at Westminster Magistrates Court.
He denied a charge of supplying the drug.
Contostavlos, who wore tight black trousers, a black top and black jacket, was forced to disclose her address to the court after her solicitor applied for it to be withheld to prevent "unwanted visitors".
But Chief Magistrate Howard Riddle ruled "the address must be given" after considering the application with representations from prosecutor Emma Scheer and the Press Association.
The singer then told the court: "Just to let you know, after it being read out, in the next month or so I might have to move to a new address."
The Crown Prosecution Service (CPS) announced last week that it had authorised the Metropolitan Police to charge the former X Factor judge with ''being concerned in'' the supply of Class A drugs.
Contostavlos's lawyer Ben Rose said last week that his client would be denying the charge and claimed she joined a line of celebrities who had been used as "fodder by greedy newspapers".
Contostavlos, 25, was initially arrested in connection with the incident with 35-year-old musician Mike GLC - real name Michael Coombs - on June 4.
She was officially dropped as a judge on X Factor days before her arrest, with Sharon Osbourne returning to the show in her place.
A Scotland Yard spokesman said the singer had been charged alongside Coombs, 35, of Enfield, who is also due to appear today.
The pair will next appear at Southwark Crown Court in central London on January 14.