They can offer you a better return because they operate more cheaply than brick-and-mortar banks.

FORBES: Three Key Advantages To Banking Online

Finally, Internet banks with the Federal Deposit Insurance Corporation (FDIC) seal are insured the same as FDIC-insured brick-and-mortar banks.

FORBES: Are Online Banks Safe?

Some brick-and-mortar banks have similar restrictions, Mr. Tumin says.

WSJ: Finding High Rates Online