Before everyone's attention drifts toward holiday parties and ski vacations, financial advisors have a number of action items they say clients must attend to first. "We have our checklist," said Diane Pearson, the personal chief financial officer with Legend Financial Advisors.

Year-end tends to be a flurry of last-minute financial moves, but it doesn't have to be. Some items on the checklist, such as matching losses against gains, may need to wait until later in the year, when the picture is clearer. But others, such as taking required minimum distribution from retirement accounts, can be done any time of the year

"A lot of what we consider year-end planning are things that people should think about all year long," said Tim Steffen, a CPA who is also director of financial planning at Robert W. Baird & Co. "But human nature being what it is, we need a deadline to get things done," he said.

Just in case you've been procrastinating, here's a year-end checklist to get through before you turn the lights out on 2015.

—By Ilana Polyak, special to CNBC.com
Posted 07 October 2015

You must start taking a required minimum distribution from tax-deferred accounts the year you turn 70½. In truth, you can wait until the year after you turn 70½, but you run the risk of having two distributions that year and paying twice the tax. Failing to take the distribution can result in big fines: 50 percent of the amount distributed, plus the tax owed, and you're still required to take the distribution. For a $10,000 distribution, you might end up with just $2,000 to spend after penalties and taxes.

"That's what I call a stupid tax," said CPA and certified financial planner Scott Bishop, director of financial planning with STA Wealth Advisors.

For that reason, advisors such as David Hollands, a CFP with Eagle Wealth Solutions, said his office tracks which of his clients have taken the distribution and pesters those who haven't. "The first time you make a mistake and forget to take it, you might get some forgiveness [from the IRS], but that's not guaranteed," Hollands said.

Late fall is also open enrollment season for health insurance at most large employers. It's the same for Medicare and the health-care exchange, Healthcare.gov. Take time to review your health insurance. Did you use all the benefits that your insurance offers? Do you need a more robust plan even if it costs more in premiums but provides greater benefits?

This is an ideal time to make sure you're using any "use-it-or-lose-it" accounts, such as flexible spending accounts that let you set aside pretax money to pay for health care–related expenses, such as prescription drugs.

"Go to the dentist and do that procedure or get a new pair of glasses," said CFP Chris Chen, founder of Insight Wealth Strategies.

In recent years the IRS has started to allow $500 a year to be rolled over, but not all employers offer this feature. Check on your company's rollover policy.

If you think you might be writing a big check to the IRS next April, one way to bring down your tax liability is by adding more money to a tax-deferred retirement plan, such as a 401(k) or 403(b) plan. You'll get the tax savings up front by lowering your taxable income.

Though stocks have floundered in 2015, some stocks have seen gains. If you're thinking of taking profits, consider ways to zero out those gains with losses. But watch out for the wash-sale rule. You cannot sell one security to book the loss only to turn around and buy it back again. You must wait at least 31 days before getting back into the same security, though you could buy something similar during that period.

As nice as it might be not to pay taxes on gains, don't drive yourself crazy trying to match up gains and losses. "If all you have are gains during the year, that's a good thing," said Steffen at Robert W. Baird & Co.

Late November and early December is the time when mutual funds declare their capital gains distribution to shareholders. But they don't make the distribution until sometime later.

Unlike individual stocks, shareholders have no control over the timing of these gains, since it's the portfolio manager, not the individual investor who decides when to sell an appreciated stock. But that doesn't mean you have to stick around and pay the tax. "If it's a large distribution, we might sell out of the fund [before the distribution is made]," said Pearson at Legend Financial Advisors.

Fall is a good time to research organizations and causes close to your heart for when you're ready to make charitable donations "instead of waiting until Dec. 15 and seeing who mails you a letter," said Bishop at STA Wealth Advisors.

It's still unclear whether Congress will extend the law allowing retirees to make tax-free transfers from their IRAs in lieu of the required minimum distribution. In years past, these extensions came late in the year, though they were retroactive to beginning of the year. The problem is, once you've taken your distribution, you can't put it back and make a charitable donation out of the IRA. Advisors recommend you make your charitable donations without regard to what Congress may or may not do.

If you think you'll be staring down a big tax bill in April, look for deductions now. Some states send their property tax bills in December, though they may not be due until January. There's no reason not to pay it in December and take the deduction against your federal income taxes for 2015. You can do the same with state income taxes and professional fees for an accountant or a financial advisor.

But don't go overboard. There are caps for itemized deductions for high earners, so you might not be able to take every deduction that comes your way. "You have to look at these deduction and ask yourself, 'Is this going to have more value for me this year or next year?'" said Steffen at Robert W. Baird & Co.