Applying the correct postage is your responsibility

Learn how applying incorrect postage can affect your mail delivery.

It is important to pay the correct postage when sending your mail

Australia Post offers several ways for you to post your mail, including through red street posting boxes conveniently located throughout Australia.

When using red street posting boxes, it is the responsibility of the sender to apply the correct postage for their items before posting them.

Please read our postage guide to learn how your item’s length, width, thickness, and weight affect the total postage cost.

Where an item’s dimensions, weight or thickness are outside what is allowable for a letter, it must be charged as a parcel.

Will my mail still be delivered if I incorrectly calculate my postage?

Australia Post can carry an item with insufficient postage that was lodged in a red street posting box, and then issue an Underpaid Mail invoice to the sender to claim the amount of the deficient postage plus a service fee. 

We may also decide to take other actions depending on the circumstances, such as withholding the item for delivery until the deficient postage is paid or seeking payment from the addressee when a sender is not identified.

Where we take such actions, we will communicate this directly.

You can read more about recovery of postage on underpaid items under Section 28 of the Australia Post Terms and Conditions (PDF 725kB)