The battery did not participate in the opening battle of the campaign at the Wilderness but soon advanced to the front lines and fired their first shots at the enemy on May 10 during the Battle of Spotsylvania Court House. Over the next two days they were heavily engaged, nearly losing their guns on May 12 during a Confederate charge which they narrowly repulsed. On May 23 they were engaged in the Battle of North Anna. During the Battle of Totopotomoy Creek on June 1, the 14th Massachusetts Battery played an important role in repulsing a Confederate assault on their section of the lines. They were again engaged during the Battle of Cold Harbor from June 6 to June 12. It took an active part in the Siege of Petersburg being moved to the front lines and engaged with enemy artillery from June 21 to 24, July 10 to 17, August 5 to 21 and on October 11. On October 25, 1864 they moved to Fort Merriam in the defenses of City Point, Virginia and there went into winter quarters.