Travel can request a Delta callback option at +1-802-231-1806 and avoid waiting for a hold on the phone call. For reservation, flight status, or any updates, you can dial 800-221-1212 and get a quick callback from Delta.com. All customers, including U.S. citizens and legal permanent residents, aged 2 and overflying from an international destination to the United States must obtain a negative COVID-19 test result within 1 day of departure and confirm their negative result by signing an attestation form.