Royal Mail postage underpayment surcharges explained

Royal Mail applies a surcharge to mail that is franked with insufficient or zero postage. The charge is the missing postage plus a per-item fee, and the most common causes are franking a Large Letter as a Standard Letter, or getting the weight or destination wrong. [FACT NEEDED: confirm the current Royal Mail zero-postage and underpayment surcharge amounts before publishing.]

Common reasons for underpayments

• Not being familiar with how the franking machine operates.
• A Standard Letter franked for an item that weighs over 100g or is over 5mm thick, which should be a Large Letter with weight-based postage.
• A C4 envelope franked as a Standard Letter instead of a Large Letter.
• Standard Letter postage used for items to Ireland (excluding Northern Ireland), which need the correct international rate.

How to avoid a surcharge

Weigh and measure every item, pick the correct format, and use a Royal Mail size guide ruler before you frank. If you would like us to add a complimentary size guide to your next order, email info@mailcoms.co.uk.

FAQs

Why has my mail been surcharged? Because it was franked with insufficient or zero postage – often a Large Letter franked as a Standard Letter, or the wrong weight or destination.

How much is a Royal Mail underpayment surcharge? It is the missing postage plus a per-item fee. [FACT NEEDED: confirm the current zero-postage and underpayment surcharge amounts from Royal Mail.]

How do I avoid surcharges? Weigh and measure each item, choose the correct format, and use a size guide ruler before franking.