The threat of the pending “fiscal cliff” and subsequent tax hikes is prompting some local companies to pay out special dividends to shareholders — including their own corporate executives — before the calendar flips to 2013.

Jan. 1 will bring the end of the George W. Bush-era tax cuts unless President Obama and Congress reach a budget agreement. As a result, the top tax rate on dividends would soar to 43.4 percent from 15 percent.

Obama has said he aims to preserve tax cuts for the middle class while raising taxes on the wealthiest Americans. Republican leaders, who initially opposed any tax hikes, appear to have softened their position in recent weeks.

Still, companies that have determined a deal is unlikely or simply won’t be favorable to large shareholders have opted to pay additional dividends in 2012 so that shareholders can lock in the existing tax rate.

Nationally, corporations such as Wal-Mart, Harris Teeter and Carnival have either moved their fourth-quarter dividend to before Dec. 31 or have announced an additional dividend before year’s end.

Nearly 100 companies have announced special dividends for the fourth quarter, according to Markit, a financial data company. The firm expects at least another 20 companies to declare dividends before Jan. 1.

“Normally you would wait until at least the first of the year to do this because then you wait [a year] for the tax bite,” said Robert J. Shapiro, a senior policy fellow at Georgetown’s business school. “If you do this now, that’s because you’re afraid of higher taxes on dividends in 2013.”

Shapiro served as undersecretary of commerce for economic affairs during the Clinton administration. He now consults for companies and governments as chairman of Sonecon, an economic advisory firm.

While Shapiro said the earlier payout can offer little material benefit to the company itself, it could be a gamble if Congress ultimately reaches a deal that doesn’t include higher taxes on dividends.

“If the rate on dividends doesn’t change, then they have forced their shareholders to pay the tax on those dividends a year early,” Shapiro said.

After the November election, directors at Reston-based Access National Bank decided to approve a special dividend worth 70 cents per share and scheduled the delivery date for Dec. 17.

“The benefit is to let our shareholders know that we’re doing our best to look out for their economic interest,” Access National chief executive Michael Clarke said. “They’re making an investment in our company for returns, and our job is to be good stewards of their capital.”

Clarke and some of the company’s other leaders will be the biggest beneficiaries. Insiders own 25 percent of the bank with Clarke himself holding the largest portion.

A report from Markit, the data company, shows that in more than half of the companies offering one-time payouts this quarter, inside owners hold more than 25 percent of the shares.

Clarke said the bank has paid a quarterly dividend to shareholders for years, even during the recession, and he expects that to continue regardless of whether a tax hike takes effect.

“Given the current investment environment, a dividend-paying stock is becoming more attractive to investors, especially one that can offer an element of growth,” he said.