Police say two people climbed onto a truck that was parked at the services at around 10pm on Sunday evening.
The truck had been on its way to the Cuadrilla site in Preston New Road when it stopped at the services near Lancaster.
One woman came down from the vehicle at around 1pm and the other came down at around 10pm on Monday.
Bethany Cole, 21 of no fixed address has been charged with offences under the Trade Union and Labour Relations Act 1992.
Louise Castro, 56, of Suddaby Close in Hull, has been charged under the same act.
Both are due to appear at Preston Magistrates Court on April 25.