There are three options :
– small letter ($1.20) : a standard business envelope (like bills come in), max size 130x240mm, max thickness 5mm, max weight 250g.
– large letter ($2.40 up to 125g, $3.60 for 125-250g; $6 for 250-500g) : can be A5 or A4 size, max size 260x360mm, max thickness for a large letter is 20mm (2cm).
– parcel ($10.60 up to 500g; $14.50 for 500g-1kg; $18.25 for 1-3kg; $21.95 for 3-5kg)
These are 2023 prices. If you are sending under 100 bread tags, a small letter should be sufficient.

100g of bread tags is about 270 tags, so weight is not usually the issue when sending small quantities, it’s the thickness you need to watch to avoid parcel rates. So the best way is to fold a piece of paper round your tags so they fit quite tightly and stay flat. Then put the folded paper into an envelope.

If you are sending a parcel, you can re-use a bag or box you already have or use an Australia Post plastic satchel or a cardboard box. We prefer not to get the packaging which has bubble wrap inside paper as this cannot be recycled because it is plastic and paper glued together.