Usage Guidelines


Usage Guidelines


To make sure your mail gets delivered, please ensure it adheres to the following:


UniversalMail Stamps are for use on INTERNATIONAL POSTCARDS ONLY


All mailing items must be able to be processed by Royal Mail machines and are therefore, required to meet the following mail format:

Mail piece format (physical requirements)


  • Maximum size: 240mm x 165mm (C5+)
  • Minimum size: 140mm x 90mm


  • Maximum: 10g


  • Maximum: 5mm
  • Minimum: 0.25mm
  • The postcard must be able to bend into an ‘S’ shape


  • Rectangular (oblong) or square
  • All four sides must be straight
  • Each corner must be 90°
  • The vertical edge must be equal to or shorter than the horizontal edge
  • Items printed in ‘portrait’ format are not allowed


The biggest reasons for mail being held up or not delivered are the following:

  • Postcards not having destinations clearly written
  • Our stamps being used on envelopes or packages – we don’t have the facility to send packages internationally
  • Our stamps being used to send mail to domestic addresses. Contractually, our stamps are for international destinations only