Postage information
Here are some useful tools and information regarding postage formats and costs.
Postage calculator
Postage formats
Letter
Means a Mailing Item, which is no larger than oversized C5 (165mm x 240mm) and no thicker than 5mm. The minimum size is 100mm x 70mm. Letters must weigh 100g or less.
Large Letter
Means a Mailing Item which is not a Letter and which is of uniform thickness across the surface of the item, whose area is no larger than 353mm x 250mm, and no thicker than 25mm. Large Letters must weigh no more than 750g.
A3 Packet
Means a Mailing Item which is not a Letter or Large Letter and which is of uniform thickness across the surface of the item, whose area is no larger than 420mm x 297mm, and no thicker than 25 mm. A3 Packet must weigh no more than 750g.
Packet
Means a Mailing Item, which is larger than A3 Packet i.e. when any one of the dimensions exceeds 297mm or 420mm or 25mm or 750g. Max weight depends on service.

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Details of letter formats and dimensions.
Letter
Min - 100mm x 70mm
Max 165mm x 240mm
Large Letter
Max weight 750g
Max 353mm x 250mm









