According to police, the disgraced cyclist left the scene of the accident before officers arrived and allowed his girlfriend to take the blame.
Documents seen by the Aspen Daily News said Anna Hansen, 33, told police she was driving, before changing her story.
Armstong, 43, who was stripped of seven Tour de France titles for doping, faces court on 17 March.
He could face a fine and up to 90 days in jail if convicted of the charges of leaving the scene of an accident and driving too fast for the snowy conditions.
Hansen, who lives in the ski resort of Aspen, was initially cited for the incident after telling police she had been driving the couple home from an Aspen Art Museum party.
She claimed to have lost control and hit two parked cars, before speaking to the owner and offering to pay for the damage, the police report said.
Officers then spoke to the valet at the event, who said Armstrong had driven away from the gala.
The charges were transferred to Armstrong on 12 January after Hansen told police the couple had made a "joint decision" to avoid negative headlines.
Hansen won't face charges because of her subsequent confession.
Armstrong was stripped of his seven Tour de France victories and banned for life from racing in 2012 by the US Anti-Doping Agency after he admitted using performance-enhancing drugs.