The travel-size edition will have a print run of 50,000 and go on sale in WH Smith Travel stores and other outlets in London targeted at commuters and travellers. It will run alongside a normal sized edition of Cosmopolitan and have exactly the same editorial content.
The trial starts with the October issue, which hits the newsstands on September 18, and is likely to be extended through January and February.
The move will be seen as a defensive one -- Conde Nast's Glamour has extended its lead over Cosmopolitan by more than 75,000 in the last Audit Bureau of Circulation and leads the women's monthly glossy sector.
While Glamour enjoyed a year-on-year increase of 23.1% to 537,474, Cosmopolitan was flat with an ABC of 463,058. The period-on-period showed an increase of 3.3% for Glamour, compared to a 1.5% decline for Cosmopolitan. Glamour is expected to extend its lead in the ABCs due out later this week.
The format change comes just two months after NatMags cut the cost of its July issue by £1 to £1.80 outside the South-East to price-match it with Glamour.
Conde Nast lampooned NatMags decision. Nicholas Coleridge, the managing director of Conde Nast, said: "After everything National Magazines have said about our Glamour format, this has to be the biggest strategic U-turn since Margaret Thatcher junked the Poll Tax. The words desperate and knee-jerk do rather spring to mind."
Duncan Edwards, the managing director of NatMags, denied that it was a response to Glamour.
"Cosmo in Greece, France and Spain are already available in both formats -- you can buy either or. This predates the launch of Glamour", he said.
He added that NatMags was committed to testing the format only on the October issue and that a decision would then be made on whether to continue retailing both sizes.
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