Like early mail exchange in the American Colonies, following Cook's contact, mail in Hawaiʻi was handled privately by employing forwarders or by making arrangements directly with a ship captain. Hawaiʻi and the US agreed on a ‘Treaty of Friendship, Commerce and Navigation and Extradition, December 20, 1849;’ among other things, Article 15 of the Treaty created an arrangement for delivery of mail.
On November 2, 1850, The Polynesian announced it was keeping a letter bag open to receive letters and promised to place on board reliable vessels any letters deposited in its letter bag. By 1850, almost all mail was being sent to/from Hawaiʻi via San Francisco to enter the mail stream there and be carried in the US mail via Panama to New York. Hawaiʻi’s first stamps (issued in 1851) included a 2-cent stamp for the newspaper rate, a 5-cent stamp for regular mail to the US, and a 13-cent stamp for mail to the US East Coast.