Emergency Assistance for Renters Act of 2021 This bill provides additional FY2021 funding for the Department of the Treasury's Emergency Rental Assistance program, which was established in response to the COVID-19 pandemic. The program provides grants to states, local governments, and territories for financial assistance to households for rent, utilities, and other housing expenses. Low-income households that are at risk of homelessness and are experiencing unemployment or financial hardship are eligible. The aggregate period of assistance a household may receive under this program may not exceed 18 months.