The CDC has issued recommendations for Fully Vaccinated People. Heres the summary (as of April 2, 2021):

Fully vaccinated people can resume domestic travel and do not need to get tested before or after travel or self-quarantine after travel.

Fully vaccinated people do not need to get tested before leaving the United States (unless required by the destination) or self-quarantine after arriving back in the United States.

https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated-guidance.html

You can see the entire CDC guidance page at:

https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated-guidance.html