A look at the pending outcomes of going over the “fiscal cliff.” (The Washington Post)

As lawmakers struggle to agree on a plan to avert the series of tax increases looming next year, many investors are taking preemptive action to get out of harm’s way.

Americans are moving to sell investment homes, off-load stocks, expand charitable donations and establish tax-sheltering gifts before the end of the year. Financial advisers and accountants say people are trying to avoid the higher taxes that will take effect in 2013 if Washington does not avert the “fiscal cliff.”

For the most part, the people moving their assets are the wealthy, who have the most to lose even if a deal is struck. Ordinary Americans also are in line for higher income and payroll taxes and fewer deductions and tax credits if the nation goes over the fiscal cliff. But since most of their earnings come through wages, there is little they can do to minimize the impact. Also, the majority of investment income earned by middle-income people comes through tax-deferred vehicles such as individual retirement accounts and 401(k)s, making the possible changes in taxes on investment returns largely immaterial.

“You’re not going to refuse your paycheck because the taxes are higher,” said Roberton Williams, senior fellow at the nonpartisan Tax Policy Institute. “The people that can make adjustments, who can change the way their world works, are the wealthy.”

Democrats and Republicans agree that they want a debt-reduction agreement that does not raise taxes for individuals who make less than $200,000 a year and couples who earn less than $250,000. But those earning more are all but certain to pay higher taxes through increased income tax rates, fewer deductions or a combination of the two.

‘Fiscal cliff’ calculator’: What it will mean for me

The maximum tax rate on long-term investment earnings would rise from 15 percent to 21.2 percent in the absence of a deal. In addition, the higher income earners will face a new 3.8 percent surcharge on investment income to help fund implementation of the 2010 health-care law.

The impending increases are reversing the normal rule of thumb for limiting the bite of income taxes. Rather than accelerating losses and delaying income, some investors are harvesting their profits now, while lower rates are sure to be in effect, and holding on to losing investments until 2013.

For the nation’s top earners, who as a group make a large share of their incomes through investment returns, those moves could have a major impact on their tax bills.

“We are seeing a lot of questions about what assets to sell,” said Debbie Haines, a partner at CST Group, a Reston accounting firm. “A lot of people are wanting to liquidate stocks that have a gain. A lot of people are harvesting their capital gains. There is also some concern that itemized deductions will be cut, and some people who are charitably inclined are thinking about making bigger donations this year. “

Also, with the tax laws covering gifts set to tighten significantly, several Washington area estate lawyers say they are facing a rush of people interested in establishing trusts that under current law allow a couple to protect more than $10 million in assets from the tax man. Impending changes in the law could reduce the gift exclusion to $1 million for an individual or $2 million for a couple.

The new limit would hit the wealthy hardest, but in regions such as the Washington area that have high housing prices, it would also hit many homeowners who do not view themselves as rich.

“If you own your home and have some retirement accounts, many people can breach that threshold,” said Patrick J. Vaughan, a Vienna lawyer who says he is swamped with new clients worried about the new tax rules. “This is going to be a very nightmarish situation thinking about all the estate taxes people are going to pay.”

An increase in the capital gains rate could potentially hit many middle-income families, particularly since it applies to the taxable portion of the profit from home sales.

“The capital gains will affect anyone with investments, whether it be stocks, business or property,” said Barry Glassman, a financial planner in McLean. “It’s not going to affect many homeowners, since they will likely have a portion of their gain free from tax. But it can and will affect people with investment and rental properties.”

Nick Chaconas, a real estate agent at Llewellyn Realtors, said he has been approached by two people in the past 90 days who are eager to sell their investment properties before the capital gains rate jumps. One of them is furiously negotiating with two potential buyers as he tries to move his North Potomac townhouse before Dec. 31.

“He figures that at least he knows what the capital gains is this year,” Chaconas said. “Come January 1st, who knows what that rate will be.”

Joan Caton Cromwell, a real estate agent at McEnearney Associates, said she suspects that the high number of fixer-upper homes listed for sale in the past two months reflects the rush to unload investment properties before year’s end.

One of Cromwell’s clients took part in the rush. He had inherited a duplex in Friendship Heights from his parents in 1997. His brother lived there for a stretch. But in September the two of them decided to list it for sale, and it sold in November.

“They were [dawdling] about what to do with it, and with all the conversations about the increase in capital gains, they said, ‘Let’s get this done,’ ” Cromwell said.