An interim timetable will be in place for the Denbigh - Ruthin - Wrexham bus service from July 12 until September 4.
Denbighshire County Council is providing cover for the X51 Service as Arriva will be unable to do so, owing to staff shortages.
There will be a reduced service during this period.
Cllr Brian Jones, the Council’s Lead Member for Waste, Transport and the Environment, said: “Owing to staff shortages, we have been making arrangements to provide an interim timetable for the X51 Service, using other operators.
“However, other operators are also facing staffing issues and the interim service will have some gaps but we will still be maintaining a daytime service to all communities.
“We would like to thank residents for their understanding at this time.”
The interim timetable is available at www.denbighshire.gov.uk/travel