Thomas Cook is to close a further 50 shops affecting just under 400 staff.
Around two thirds of the shops closing are Thomas Cook stores and a third are Co-operative Travel.
It is the latest round of shop closures announced by the company in the last year as it reviews its retail network.
It represents the largest single round of shop closures since 2013 when Cook announced it was shutting 195 high street stores.
Staff were informed on Thursday and today (Friday).
The stores which are affected are either in close proximity to other stores or located where a decline in footfall has impacted profitability, the company said.
Where there are two stores in the same town or in close proximity, staff at both retail outlets will be put under consultation.
The company hopes to redeploy a large proportion of the staff affected either in other shops or elsewhere in the business.
The closures will take place between now and March 2018.
The closures follow a rise in the number of holidays booked online – in 2017, 47% of its holidays were booked in store while web sales in the UK grew by 27%. The company said this demonstrated progress in its strategy to become an omni-channel business.
After announcing its year-end results last month, chief executive Peter Fankhauser acknowledged the shift towards online was moving “faster than expected” and the business would have to “follow the customer and be where they expect it to be”.
“If we get that shift then we have to manage those stores for profit,” he said. “If the stores are unprofitable then we have to check whether we still want to have that store or close it.”
Cook has closed 84 shops since last October. This latest round of closures will take its total retail network to 640.
As well as closing shops Cook has opened two new Discovery stores in high footfall areas, such as shopping centres, and refurbished 10 in the last 12 months.
Director of retail and customer experience Kathryn Darbandi said: “We continually review our network of stores across the UK to make sure we’re offering customers the best of Thomas Cook, and it is clear that to succeed we have to operate as a truly omni-channel business.
“We’re one Thomas Cook to our customers and we will offer them a world-class service whichever channel they chose to book, be that retail or online.”
More: Thomas Cook announces plans to shut 39 stores [Feb 17]
Thomas Cook to close 17 more shops [Apr 17]