December saw the highest number of days lost to strike action in over a decade, according to new data.
Figures from the Office of National Statistics (ONS) said there were 843,000 working days lost in December because of labour disputes.
That figure is the highest since November 2011, when 997,000 days were lost due to industrial action.
Transport and communication sectors remained the most impacted by the strikes towards the end of last year.
There was also a “large contribution” from the health sector, according to Darren Morgan, director of economic statistics at the ONS.
Already this month, transport workers and university lecturers across the UK have walked out over employment and pay disputes, with further action planned by both sectors.
Amazon workers at the Coventry fulfilment centre are also planning two weeklong strikes at the start and middle of March.