From the rest of the United States, sending a 1-ounce mail to Hawaii costs 49 cents. USPS shipping to or from the mainland does not incur any additional fees because postal prices are uniform across all 50 states.
The current postal fees for letters are 21 cents per ounce over the first and 34 cents for postcards. Shipping costs for parcels may vary based on distance, however USPS Flat Rate Priority Shipping charges to non-continental states remain the same. However, delivery of letters crossing the ocean may take significantly longer than usual.
