Avoid Surcharges for Mailmark Letters and Large Letters

Here at ADM we encourage our mail order and membership organisation clients to use Mailmark where possible for their mailings as it’s the cheapest way to post a Letter or Large Letter.

Mailmark items make up 82% of Royal Mail Wholesale volume including magazines, newsletters, brochures and catalogues. Items mailed using Downstream Access companies such as The Delivery Group or OnePost can also be Mailmarked.

Royal Mail uses scanning software with OCR (Optical Character Recognition) to allow mail to be machine sorted. This only works if addresses are printed in the right size and font and in the right place so direct mailing pieces must adhere to set Mailmark guidelines.

Royal Mail Mailmark Surcharges

Royal mail has been making changes to the Mailmark Letter and Large Letter specifications to enable them to automate the processing of mail more efficiently through their system. Under the new changes, mailings which do not comply with these guidelines, may be subject to a Surcharge.

Improving Mailmark Barcode Read Rates

We have been working with Royal Mail to improve the barcode read rate performance of Mailmark Letters and Large Letters. We have been part of Royal Mail poly-wrap trial where we investigated the causes of poor barcode readings with mailings wrapped with LDPE polywrap and 100% compostable potato starch biowrap.

Poor barcode read rates were linked to barcode print quality, barcode and delivery address location and the quality of the outer wrap used.

Mailmark Specifications Published

Royal Mail recently published 53 pages of Mailmark guidelines. These highlight Letter and Large Letter specification requirements and categorises them as either:

  • Mandatory
  • Recommended High Risk
  • Recommended Low Risk.

Whilst some specifications are black and white, there are so many grey areas and endless variations – every mailing will be different, and it isn’t crystal clear when a Surcharge may be applied yet. There are differences between Letters and Large Letters given the way they are processed through the Royal Mail system.

Here at ADM we want to avoid our Clients’ printed material arriving which is outside the guidelines. We work with our Clients at the design change and guide them through the Mailmark minefield. A Surcharge could add thousands of pounds to their mailing costs and we help them avoid it with the right guidance.

Getting it right, first time

1.Getting the Delivery Address Right

Mailer Defined Information

The Delivery Address must be a PAF address and it must be on the same side and the same orientation as the PPI. It must be positioned below and to the left of the PPI. There are preferred fonts and any text should be 10-12pt.

No other addresses and nothing else which can be construed as looking like a delivery address must be printed on the Letter (with the exception of the Return Address).

2. Getting the 2D or 4-State Barcode Right

ADM’s preferred Mailmark barcode is the 2D Mailmark. It must not be printed in the Letter border area.

Print – No other text, patterning, or graphics must be printed in an area around the 2D barcode that is at least 4 times the module size (i.e. at least 2mm when the module size is 0.5mm, and at least 2.8mm when the module size is 0.7mm).

3. Getting the Return Address Right

Position – The Return address must be on the front of the Letter in the top left corner (with no element closer than 75mm to the right edge and no closer than 12mm to the Delivery Address.)

Font Style and Size – The return address must be in Title Case using 10-12pt Letter Gothic or Lucida Console font.

Content – The return address must be prefixed with the words Return Address and it must be a PAF address that includes a premise element, thoroughfare element, locality, and the postcode. The addressee information must be included on the second line of the return address block and the number of characters per line of the return address block should not exceed 64 characters.

Royal Mail Mailmark Large Letter Return Address

4. Getting the Access PPI Right

Position – The Access PPI must be located on the front of the Letter, above and to the right of the Delivery Address and in the top right corner of the Letter in the Indicium area shown below. This area is 75mm long & 40mm high.

Print Quality – The Access PPI should be printed at a minimum resolution of 300dpi and should be clearly visible against any printed background.

Royal Mail Mailmark Letter clear zones PPI

5. Getting the Outer Wrap Right

The material and method used to wrap a mailing can affect the machines’ ability to read the Mailmark barcode, recipient address and return address information.

For example, whether your mailing is being wrapped with LDPE Polywrap or the more environmentally friendly 100% compostable potato starch biowrap, the carrier sheet design needs to be mindful of where the outer wrap’s seam is as this will affect the machinery’s ability to read what’s behind it.

Get in touch today

Whether you are sending a Letter or Large Letter, whether it’s wrapped or being mailed naked, talk to us at the design stage.

We work closely with Royal Mail and have the knowledge to make sure your design complies with the new guidelines.

Get in touch today on 01384 215790 or at  info@advanceddirect.co.uk.

 Mailmark Facts

  • Mailmark applies to Letter and Large Letter formats.
  • Mailmark brings mail, technology and business information together.
  • Royal Mail uses scanning software with OCR to allow mail to be machine sorted.
  • The 2D or 4-state barcodes are read by the Royal Mail’s machines as mail passes through their system.
  • Letters and Large Letters are treated differently within the Royal Mail system – Large Letters lie flat on the belt and are read from above while Letters are held upright and read from the side.
  • Web-based reporting from an online analytics dashboard is available.
  • The reports show predicted delivery, volumes and how well the mailing is performing at the batch level.
  • Errors can also be reported at the item level.


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