With the Aleutian campaign over, New Mexico returned to the west coast and was refitted at Puget Sound Navy Yard. On return to Pearl Harbor on 25 October she began to prepare for her next major role, the invasion of the Gilbert Islands. As a part of the Northern Attack Force (Task Group 52.2) she commenced bombarding Butaritari on 20 November and continued to provide support until departing for Pearl Harbor on 5 December. The task group then sailed to the Marshall Islands on 12 January 1944 and began bombarding Kwajalein and Beye between 31 January through 7 February. On 20 March 1944 four battleships, including New Mexico, shelled Kavieng, New Ireland, as a diversion from the Army invasion of Emirau Island.

New Mexico was again used for pre-invasion bombardment and fire support as part of Task Group (TG) 52.1 during the invasion of the Marianas in June 1944. On 14 June she bombarded Tinian, Saipan on 15 June, and Guam on 16 June and provided AA defense on 18 June. During the Battle of the Philippine Sea, from 19 to 20 June she protected transports in the area. She escorted more transports to Eniwetok and between 9 to 12 July she protected escort carriers. On the latter day she began her pre-invasion bombardment of Guam which she continued until 30 July.

Between August to October 1944 New Mexico was overhauled at Bremerton. On returning to the warzone she became a member of TG 77.2 for the Leyte Gulf operations beginning in 22 November. The task groups were subjected to heavy air attacks and kamikaze attacks but she went unscathed. On departing the area on 2 December she sailed to Palaus and en-route escorted an assualt convoy heading to Mindoro, where she remained for the next two days before continuing to Palaus. TG 77.2 then headed to support the invasion of Luzon at Lingayen Gulf the first week of January 1945. While bombarding on 6 January a kamikaze hit the bridge killing her captain (Captain Fleming) and 29 other men while injuring another 87. She was determined in her role and continued to provide support for the landings.

Once the Luzon operation was complete she underwent repairs at Pearl Harbor. With repairs complete she departed for Ulithi to prepare for the invasion of Okinawa in March 1945. As a part of Unit 5 in Task Force 54, she begain shelling Okinawa on 26 March and contined into April. On 11 May she destroyed eight suicide boats and the next night she was approaching her berth when two kamikazes attacked her. One of them hit her with a bomb and the other aircraft smashed into her killing 54 men and wounding 119. Within a half hour the fires were extinguished and she soon departed for Manila for repairs. With repairs complete she bagan preparing for the invasion of the Japanese home islands in Saipan but the war ended on 15 August so she sailed to Okinawa for occupation duties. On 27 August she supported the occupation of Atsugi Airfield before sailing into Toyko Bay as a member of Halsey's Task Force 38 to witness the surrender on 2 September.

New Mexico arrived at Boston on 17 October and was decommissioned on 19 July 1946. On 13 October 1947 she was sold for scrap to Lipsett Inc of New York. She was awarded six battle stars for her service in World War II