Werth was convicted last month in Fairfax County and sentenced to 10 days in jail, but he appealed his conviction to Circuit Court.
The Washington Post reported that Werth entered a guilty plea Thursday. Werth will serve his sentence on weekends to minimize disruption to his rehabilitation following shoulder surgery.
It is not unusual in Virginia for judges to impose short jail sentences in cases where speeds exceed 100 mph.
At Werth's initial trial, a state trooper testified he paced Werth at 105 mph on the Beltway in the McLean area for about a half-mile on an early Sunday morning in July.