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Exhibit 99.1 PRESS RELEASE October 19 , 2021 , 8:00 AM ET Fairfax , Virginia Contact : Jeff W. Dick , Chairman & CEO ( 703 ) 481-4567 MainStreet Bancshares , Inc. Reports Record Strong and Steady Third Quarter 2021 Earnings - October 19 , 2021 MainStreet Bancshares , Inc. ( Nasdaq : MNSB & MNSBP ) , the holding company for MainStreet Bank , reported net income of $ 4.8 million for the third quarter of 2021. Year - to - date net income through September 30th is $ 17.4 million , and year - to - date results represent : 13.14 % return on average equity 1.37 % return on average assets $ 2.09 earnings per share of common stock ( basic and diluted ) $ 20.64 per common share book value Year - to - date net interest income through September 30th of $ 39.7 million is up 20.5 % over the same period last year . The Company's cost of funds for the quarter - ended September 30 , 2021 , is 1.03 % , down 32 % from the same period a year earlier . The Company is on - track to continue reducing funding costs . The Company's efficiency ratio is 54.7 % for the nine - months ended September 30 , 2021 . Total assets remain steady through the year at $ 1.7 billion . Net loans of $ 1.2 billion include approximately $ 264 million of new commercial loans and advances and $ 86 million of new Paycheck Protection Program ( PPP ) loans . The table below provides a reconcilement of gross loans , inclusive and net of Paycheck Protection Program ( PPP ) loans . Asset quality continues to be strong with non - performing assets representing a negligible seven hundredths of a percent of total assets on September 30 , 2021 . Reconcilement of Gross Loans through September 30 , 2021 Gross Loans ( millions ) Gross Loans Net of PPP ( millions ) % Gross Loans % Gross Loans Gross loans 12/31/2020 New loans & advances - Repayments Sold loans * $ 1,300 $ 1,164 $ 351 27 % $ 264 23 % $ 364 -28 % $ 229 -20 % $ 30 $ 30 Gross loans 9/30/2021 $ 1,257 $ 1,169 ALLL 9/30/2021 $ 11 $ 11 + PPP loans ** $ 88 Net loans 9/30/2021 $ 1,246 $ 1,246 * Sold loans represent the amount of loans sold for concentration risk management purposes . The loans that were sold yielded a net premium on sale . ** Already included in Gross Loans . Non - interest - bearing deposits represent 34 % of the $ 1.4 billion in total deposits . Seventy - six percent of total deposits are core deposits .