The former X Factor star’s car collided with a Saab outside Southgate tube station on 10 September last year.
The singer was also charged with dangerous driving, a Metropolitan Police spokesman confirmed on 7 March.
She has been released on bail and will appear at Highbury Magistrates Court on 4 April.
A conviction for drink driving could see the former N-Dubz singer banned from driving for up to a year, while a conviction for dangerous driving would result in an obligatory ban of one year.
The crash took place at a roundabout outside the tube station shortly before midnight.
Officers were called and Ms Contostavlos was breathalysed at the scene. The singer was arrested and held in custody before being released on bail pending further enquiries.
Ms Contostavlos had taken possession of the sports car just days before the incident.
The singer was a judge on ITV singing talent show the X Factor from 2011 to 2012.
Prior to that, she was a member of the London hip-hop group N-Dubz. They formed in 2000 and confirmed their split in 2012.