Travel to Alaska requires testing for COVID-19; or alternately, a 14-day quarantine upon arrival. Specific time frames are specified for the test. Caution: Alaska accepts only molecular-based tests such as the PCR tests – antibody/serology tests are not accepted.
Travelers must also complete a State of Alaska Travel Declaration Form.
For the details, see https://www.travelalaska.com/Planning/Tips/COVID19.aspx