Maj Mills was born in Subiaco, Western Australia and raised in Chesapeake, VA. Maj Mills attended college at the Virginia Military Institute and graduated in 2011. Maj Mills reported to TBS in March of 2012 and was subsequently assigned the MOS of Financial Management Officer.

In May of 2013, Maj Mills reported to II MEF as the Command Element budget officer. In April of 2014, Maj Mills reported to the 24th Marine Expeditionary Unit for duty as the MEU budget officer. Upon return from deployment in July of 2015, Maj Mills reported to 2D MLG for duty as the Deputy Comptroller. While at the MLG, he was promoted to the rank of Captain.

In August of 2016, Maj Mills PCSed to Quantico, VA where he attended resident Expeditionary Warfare and augmented as an instructor at Officer Candidate School during the summer of 2017. In September of 2017, Maj Mills moved to Okinawa, Japan for duty as the III MIG Comptroller. Maj Mills PCSed in the summer of 2019 to Parris Island, SC. While stationed at Parris Island, Maj Mills was the Lead Series Commander for Delta Company and then the Headquarters Company Commander at Headquarters and Service Battalion.

In November of 2020, Maj Mills was selected for his present rank and then received orders to MARCENT. Upon arrival to MARCENT in June of 2021, Maj Mills filled the position of Future Plans and Programming Officer in the MARCENT G-8. In October of 2021, he was promoted to the rank of Major.