Workers spend on average 75 minutes a day travelling to and from work in London, compared nationally with 52.8 minutes, the TUC said.
Wales sees the fastest commutes, an average of 41.4 minutes travelling, down 4.6 minutes since 2006.
The study compares pre-recession travel times of 2006 with those of 2012 and found the average commute was the equivalent of five weeks a year.
The TUC analysed the figures from the Labour Force Survey to mark Commute Smart week.
The study found that men working in the east of England saw the sharpest rise in travel times - up 3.8 minutes to 65.2 minutes.
But in London even though men spend just above 77 minutes commuting, the figure has fallen by 1.8 minutes since 2006. The study attributed the drop to an increase in part-time work, especially among men.
The trend was bucked by the capital's women workers who saw their travel times rise by three minutes to 72.8 minutes.
The TUC's General Secretary Brendan Barber said: "With rising transport costs far outstripping pay rises, reducing the number of peak-time commutes would save both time and money for hard-pressed workers.
"Recent trends suggest there is a link between long commute times and longer hours in the office, with the growing number of men in part-time work having shorter journeys to work.
"This trend is concerning if it means part-time workers and those needing to balance work with caring responsibilities are being excluded from certain types of jobs."
Phil Flaxton, chief executive of Work Wise UK, urged employers to "revise tired working practices" and adopt "flexible approaches to people management".
Londoners face the longest average daily commute in the UK, a study found.