CDC recommends travelers get tested with a viral test 1-3 days before traveling internationally. See CDC’s Testing and International Air Travel for more information. Also, get tested 3-5 days after international air travel AND stay home for 7 days. Even if you test negative, stay home for the full 7 days. If you don’t get tested, it’s safest to stay home for 10 days after travel.
For domestic travel, CDC recommends travelers consider getting tested with a viral test 1-3 days before travel. Also consider getting tested 3-5 days after travel AND reducing non-essential activities for a full 7 days, even if you test negative. If you don’t get tested, consider reducing non-essential activities for 10 days after travel.
Testing does not eliminate all risk, but when combined with precautions like wearing masks, social distancing, and handwashing, it can make travel safer by reducing spread on public transportation, in airports, and at destinations.