Underpaid Mail Surcharges on Mailmark Meters: What You Need to Know

If you frank the wrong amount of postage, Royal Mail applies a surcharge for the underpayment. Your mail is still delivered, but the underpayment is recorded, passed to your meter provider (for example Pitney Bowes) and shown on your next postage invoice. You can avoid most surcharges by choosing the correct format and weight, sending Republic of Ireland mail as international, and making sure the address is clear and correctly positioned.

When franking your mail you need to pay the correct amount of postage. If you mistakenly frank the wrong amount, a Royal Mail surcharge will apply for the underpayment.

If Royal Mail identifies that you have accidentally underpaid, your post will still be sent. The underpayment details are captured and provided to your meter provider (for example Pitney Bowes) and detailed on your next postage invoice. If you want to discuss an underpayment surcharge, please contact Royal Mail directly.

What can I do to prevent surcharges?

Choose the right size option when franking letters and large letters

Large Letters measure up to 353mm x 250mm x 25mm and can weigh up to 750g. Select the Large Letter option on your franking machine – not the Letter option – when franking larger letters up to this size.

More information can be found on the Royal Mail size and weight guide.

If you send mail to the Republic of Ireland, send it as international post

Letters and parcels posted to the Republic of Ireland are often sent as domestic, but the Republic of Ireland is not part of the UK. If the Irish address has a BT postcode it is domestic mail; if not, it should be sent as international post.

For more information on international destinations, visit Royal Mail international zones.

Address not visible or destination unclear

• Ensure the envelope is the right size for the contents.
• Ensure the address is positioned correctly. If you use an inserter, make sure it is set up to insert the contents correctly. If you use a Pitney Bowes inserter and need support, contact us to arrange a service visit.
• Ensure the address field clearly identifies the destination country.
• Segment international mail from domestic mail.

Frequently asked questions

What happens if I underpay postage on a franking machine?

Royal Mail still delivers the item, but records the underpayment and passes it to your meter provider (for example Pitney Bowes), where it appears as a surcharge on your next postage invoice.

How can I avoid franking surcharges?

Select the correct format and weight (for example Large Letter rather than Letter), send Republic of Ireland mail as international, and keep the address clear and correctly positioned.

Is Republic of Ireland mail domestic or international?

International – unless the address has a BT postcode (Northern Ireland), which is treated as domestic mail.

Who do I contact about a surcharge?

Royal Mail handles underpayment surcharge queries directly.