Territorial Judgeship Retirement Equity Act of 2021 This bill lowers the age and service requirements for a district court judge in Guam, the Northern Mariana Islands, or the Virgin Islands to receive a retirement annuity and be eligible to serve as a senior judge. Under the bill, a district court judge in one of these territories may receive a retirement annuity after having served for at least 10 years and reaching 50 years of age, along with meeting other requirements. A retiring judge may serve as a senior judge if the judge (1) has served for at least 15 years, or (2) has served for at least 10 years and is at least 65 years old. Current law generally requires a higher age and, in certain cases, a longer length of service before a district court judge in one of these territories may receive an annuity and obtain senior status. The bill also lowers various requirements for such a district court judge to receive an annuity if the judge retired, or was removed, due to a disability.