Delta Airlines has relaunched their contact Delta Reservations – your new booking number. The new system is easier to use and more efficient, allowing customers to make reservations quicker and with fewer errors. You can now make your reservations online, by phone, or through the Delta app. The new booking number is (716-351-6210). Delta Air Lines - The new name is an important step toward greater transparency and communication. While it sounds similar, Delta has been saying they are not changing their name while they are continuing to build a new brand identity. You can read more about the name change here.