The length and width of the large letter category remain unchanged, at 353mm x 250mm, slightly bigger than A4. The more generous thickness will mean mailing most magazines and brochures, and items containing CDs or DVDs, will fall into the large letter category and not the higher-cost packet category.
In addition, Royal Mail has increased the number of weight bands in its business tariffs for large letters to four from two and those for packets to three from two. Prices above 251g for Mailsort, Walksort and Presstream would increase per gramme.
For Response services, a special maximum thickness of 35mm applies to the large letters category.
The new pricing proposals take account of separate new Royal Mail prices to be introduced from April 2005, but Royal Mail said the major changes were made to accommodate many of the issues raised by business customers likely to be affected.
Royal Mail first applied to Postcomm with the idea for sized-based pricing in August 2003. The new pricing proposals need to be approved by Postcomm and can not be implemented before April 2006.
Postcomm said it would release a new document responding to the new pricing proposals and to industry concerns about size-based pricing in the next two weeks.
David Robottom, the DMA's director of postal affairs and industry development, said that the thickness increase seemed beneficial, but Royal Mail had still not made a convincing case for size-based pricing and its correspondence to its internal costs.
A spokesman for the Periodicals Publishing Association said the association was liaising with Royal Mail and would make a statement later today.
The increased thickness allowance is good news for magazine publishers, whose objections about Royal Mail's previous proposals led to the PPA and Royal Mail thrashing out a deal in November that increased the leeway on the thickness of large letters.
Lorna Clarkson, Royal Mail's commercial pricing director, said: "These proposals don't affect the universal service -- the geographic cross-subsidies that enable us to operate a 'one-price-goes-anywhere' system will remain. The biggest effects will be felt by business customers -- who will be targeted by competitors when the market opens fully in January 2006."
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