More than 70 financial institutions have announced they will raise wages or offer bonuses to employees after the tax law’s passage, including big firms such as Bank of America and community banks such as Bank of the Ozarks. All told, those institutions account for about half of the companies that have promised raises or bonuses since President Trump signed the bill into law, according to a running list by Americans for Tax Reform, a group that advocates low taxes.

The payouts to workers reflect a small slice of the windfall that banks large and small are in line to receive. The law includes a reduction in the corporate rate to 21 percent from a high of 35 percent last year, as well as a 20 percent deduction for income from pass-through companies. One-third of all community banks are organized as pass-throughs, according to the Independent Community Bankers of America, which represents those firms and was among the groups pushing for a lower pass-through rate.

Analysts projected the financial industry would reap some of the largest benefits from that reduction given that banks typically paid much higher effective tax rates in the past than many other industries, like manufacturing.

The boon for banks comes as the industry begins to regain some of its swagger in the wake of the financial crisis and as it seeks to roll back some of the post-crisis regulations put in place by the Obama administration under the 2010 Dodd-Frank law.

Officials at top banks have mostly showered Mr. Trump with praise for his economic policy agenda, which they say is expanding growth. Jamie Dimon, the chief executive of JPMorgan Chase, called the new tax law a “significant positive outcome for the country” in a news release accompanying the bank’s earnings on Friday.

The gains come despite a one-time hit of $2.4 billion that JPMorgan Chase reported in the fourth quarter, the result of a provision in the law that forces companies to pay a one-time tax on profits that are held overseas.

Other large banks will report earnings on Tuesday and are expected to similarly reveal large savings from the tax overhaul.