The Evening Press in York is the latest of the dwindling number of evening broadsheets to switch to tabloid format.
The paper has published a Saturday tabloid since 1997 and now plans to change the size of the Monday to Friday editions in the autumn.
In April, the Huddersfield Examiner changed to tabloid after 152 years as a broadsheet, and the Evening Gazette, in Middlesbrough, is to downsize in September.
By the end of the year, the Halifax Evening Courier and the Belfast Telegraph are expected to be the last broadsheet evening papers in Britain.
Evening Press editor Kevin Booth said: “The Saturday sale is not traditionally the strongest for evening newspapers, but ours has held up well, providing a good indication that our readers like the compact format. The overriding factor behind the change was the demand from readers and advertisers.
“From a reader point of view, people find the broadsheet unwieldy and difficult to handle and that’s come across in the communications we’ve had from them.
“The compact format will give us a greater colour facility, which appeals to advertisers.”
Booth said staff were informed of the change at a series of workshops and would be given training on “writing to length” for the compact.
But he added: “I’m keen that as part of the change we maintain an extended read and that there will be stories, backgrounders and analyses that run beyond the normal tabloid story length.”
By Dominic Ponsford