The Atlantic Union Conference of Seventh-day Adventists (originally called Eastern Union Conference) was organized on April 16, 1901, at the thirty-fourth General Conference session held at Battle Creek, Michigan.

It was renamed Atlantic Union Conference at its first biennial session held at the church (Village) in South Lancaster, Massachusetts, November 27 to December 5, 1901.

It is the headquarters for the Seventh-day Adventist Church in the Northeastern Region of the United States and Bermuda and is composed of six conferences (Bermuda, Greater New York, New York, Northeastern, Northern New England and Southern New England) covering the states of Connecticut, Maine, Massachusetts, New Hampshire, New York, Rhode Island, Vermont, and the island of Bermuda.

The headquarters for the Atlantic Union Conference is located in South Lancaster, Massachusetts and houses the offices of the president, executive secretary, treasurer, two vice presidents, departmental personnel and office secretaries.

The officers and departmental directors provide administrative leadership for more than 96,622 of the approximately 13.5 million members of the Seventh-day Adventist Church and, in addition, work closely with its college–Atlantic Union College, located in South Lancaster, Massachusetts, eight academies, 64 elementary schools, many community service centers, summer camp programs geared to accommodate children, youth, adults and the entire family, and two van ministries: one in the New York City area and the other in Stoneham, Massachusetts.