Bank of America Corp. remained atop the U.S. deposit throne for the third year in a row as the industry's heavyweights continued to win market share.

Bank of America's total deposits grew 28.0% year over year to $1.747 trillion, according to the Federal Deposit Insurance Corp.'s annual Summary of Deposits survey as of June 30. But the nation's largest bank by assets, JPMorgan Chase & Co., gained some ground with deposit growth of 30.0% over the last year. Both banks outpaced the industry aggregate of 21.7% deposit growth, which was juiced in the first half of 2020 by extraordinary government relief efforts in response to the COVID-19 pandemic as well as corporations tapping credit lines.

The pair of giants continue to separate themselves from Wells Fargo & Co., which lost 62 basis points of market share. And as a group, the top 15 largest banks continued a long-running trend of taking market share from smaller banks, gaining 145 basis points over the last year to 56.2% of all bank and thrift deposits.

Large banks have generally attributed their market share gains to technology investments as more consumers bank online and via mobile devices. Truist Financial Corp. executives cited fintech investment as a primary catalyst for its merger of equals, which put the bank at No. 6. Before the deal, BB&T Corp. and SunTrust Bank were the No. 11 and No. 12 banks, respectively, by deposits in the 2019 Summary of Deposits.

Meanwhile, 12 of the top 15 banks reduced physical branches last year, and the other three companies — Charles Schwab Corp., Morgan Stanley and Goldman Sachs Group Inc. — all operate "branch-lite" models with just 11 branches for all three banks combined.

Across the U.S., banks and thrifts closed over 1,300 branches in the last 12 months to June 30. Meanwhile, total deposits grew 21.7% to $15.589 trillion.

At the state level, Texas had the highest deposit growth at 55.6%, followed by North Carolina at 36.6%. On the other hand, deposits in Nevada dropped by almost 60%. Much of the change in deposits in Nevada and Texas can be attributed to Charles Schwab, which closed a couple branches in Nevada, dropping its deposits in the state by $198.48 billion. Over the same period, the bank entered Texas, driving a $291.67 billion increase in total deposits.