A three-month strike by porters at Ninewells Hospital did not cost NHS Tayside a penny.
In April, 117 porters, including staff at the city’s Royal Victoria Hospital, went on strike in a dispute over back pay.
They claimed to be owed millions of pounds after being wrongly graded 10 years ago.
The continuous strike followed a series of one-day actions and failed talks with health bosses.
But despite losing the porters’ services for about 12 weeks, the health board said there had been no additional cost because helpers had covered some 580 shifts every week to ensure minimal disruption.
In a freedom of information request, NHS Tayside said: “During the period, cover for porter duties was not always provided on a shift by shift basis.
“The cover provided was based on the necessity of the duties to be carried out.
“During the period approximately 580 porter shifts each week were covered.
“NHS Tayside has incurred no additional financial costs during the period as porter duties have been covered by staff helpers providing their assistance in their own time and individual members of other staff groups who have taken on tasks in addition to their normal duties.
“One hundred and 17 porters took industrial action.”
The strike ended in June after union members accepted a “compromise” offer of increased wages.
Chief executive Lesley McLay said at the time: “The safe and effective delivery of care to our patients has always been our priority throughout this dispute.
“Staff helpers have made a remarkable contribution in keeping our patients safe and ensuring they received all the treatments and diagnostics they required during this action and we remain very grateful to them.
“We look forward to welcoming our porters back into our hospitals.”
NHS Tayside also revealed that one porter was suspended during the strike, later being reinstated.
He was Nicky Lamond, who was suspended in March after posting a placard on the internet which stated how he was “sick” of NHS Tayside HR director George Doherty.
He was understood to have received a written warning after a disciplinary meeting in May.
During the strike, some visitors to the hospital made claims that bags of rubbish had been left lying in corridors as a result of the strike.
The health board insisted the bags had been left in non-clinical areas and were awaiting collection at the time.