If You're Unvaccinated, You Can't Go to This State Without Quarantining
Without proof of vaccination, you'll need to quarantine or get tested first.
The vast majority of U.S. states have dropped quarantine and testing requirements for entry, but for some interstate travel, you would benefit from carrying your vaccination card with you. If you're looking to visit the country's most tropical destination, you may be forced to quarantine if you're not vaccinated. Hawaii is now requiring tourists to either show proof of vaccination against COVID, quarantine, or get tested according to the state's specific protocol if they want to travel there.
According to the Associated Press, Hawaii is currently the only state with any kind of vaccination requirement. On June 24, Governor David Ige released a statement saying the state will no longer enforce testing and quarantine requirements for domestic travelers who are fully vaccinated beginning July 8.
In order to avoid the testing and quarantine when traveling to Hawaii, you have to upload the Centers for Disease Control and Prevention (CDC) vaccination card that you received when you got your shot to Hawaii's Safe Travel Program website. You also have to bring the card with you to be checked upon arrival.
If you don't have a CDC vaccination card that proves that you've been fully vaccinated in the U.S., you'll have to either quarantine or adhere to Hawaii's testing protocol. To avoid the mandated 10-day quarantine upon landing in Hawaii, you can opt to get tested for COVID. The test must be taken 72 hours from the final leg of departure, with the negative results uploaded to the Safe Travels platform or printed out before departing for Hawaii.
Some people, including certain politicians, are adamantly opposed to using proof of vaccination as a requirement for entry anywhere. The AP notes that more states (18) have banned proof-of-vaccination policies than have created programs for people to display their vaccination status on their phones to gain admittance to places easily.
As of now, New York, California, and Louisiana are the only states that have a way for residents to digitally display proof of vaccination. However, these states don't mandate the use of these systems, per the AP.