Postage Rates 2024 Large Envelopes. Priority mail flat rate ® products let you ship packages up to 70 lbs to any state at the same price. The postage rate for postcards will remain at 56 cents.
The baseline postage rate to mail a flat/large envelope has increased from $1.39 to $1.50 in postage. Use our online calculator to estimate the postage price and delivery time to send your letter within australia.