Canada Post Lettermail - Size Guide (Max Sizes)

Canada Post Lettermail is broken down into 2 categories : Standard Lettermail (less than 50g) and Non-Standard / Oversized Lettermail (less than 500g), which have different size limits. 

To be eligible for Canada Post Lettermail, your package must fit within the respective Canada Post Lettermail slots without needing to be forced or catching along the sides of the Lettermail slot. Standard Lettermail slot measures 5mm and Oversized Lettermail slot measures 20mm.

Standard Lettermail - Maximums

  • Must be less than 50g
  • Canada - 245mm x 156mm (9.6 inches x 6.1 inches)
  • USA / International - 235mm x 120mm (9.2 inches x 4.7 inches)
  • Must be less than 5mm (0.2 inches) thick

*Additional requirements for type of item, check out our Shippable Items Guide.

Non-Standard / Oversized Lettermail - Maximums

  • Must be less than 500g
  • Canada / USA / International 380mm x 270mm (15 inches x 10.6 inches)
  • Must be less than 20mm (0.78 inches) thick

Check out our handy Lettermail postage Rate Guide with weight based stamp recommendations.

Lettermail That Exceeds Canada Post Limits
It is important to note that items mailed outside any of the size requirements may be:

  • Returned to sender, with no refund of purchased postage
  • Delivered to the recipient, with cash due on delivery for the full amount of calculated parcel shipping costs (less Lettermail postage paid)
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