Most people dream of retirement long before they get there. Perhaps you imagine hours spent on the golf course, taking a class on a subject that has always intrigued you or volunteering for your favorite cause. Of course, that's the idealized version of retirement. And then there's reality.

Kiplinger's asked financial planners from the National Association of Personal Financial Advisors what retirement surprises their clients most often encounter, and queried our Facebook community as well, to come up with this list of five top financial surprises. Preretirees, you are forewarned.

This story was updated in January 2013.

5 Costly Retirement Surprises

The cost of health care came up most often as a top retirement challenge among retirees on our Facebook page. According to Fidelity Investments, the average 65-year-old couple will spend about $400,000 out-of-pocket throughout retirement until age 92, not including long-term-care costs.

Those new to Medicare may find it's more costly than they bargained for, too. While Part A of traditional Medicare, which covers hospital benefits, is free, you'll pay a premium for Part B to get coverage for outpatient services and a premium for Part D to get prescription-drug coverage. Add in the premium for a private Medigap policy, which helps cover the costs that Medicare doesn't cover, and a couple can end up paying $6,500 a year in Medicare premiums alone.

High-income beneficiaries get an extra shock -- they are subject to a premium surcharge. Even if your income isn't always high, you can land yourself in surcharge territory if you spike your income in one year with a Roth conversion, for example, or exercised stock options. The surcharge starts to kick in if your annual adjusted gross income (plus tax-exempt interest income) tops $85,000 if you are single or $170,000 if you are married filing jointly.

Keep in mind that Medicare does not cover long-term-care costs – an additional expense you must plan for. See Kiplinger.com's Special Report: Navigating Medicare and Special Report: Long-Term Care to learn more.

Health Care Costs

You no longer have to budget for work clothes or commuting. But you may have to start paying for some things that you used to receive as perks through work, such as a company car, meals, travel or computers. "Small business owners and professionals who retire are often surprised how many of their expenses were picked up by their company," says Bert Whitehead, president of Cambridge Connection, in Franklin, Mich. "It is a jolt when they discover how much it adds up to."

Many retirees plan to see the world in their first few years of retirement, but the costs of transportation, lodging and entertainment can add up quickly. Retirees' actual "travel budgets tend to be at least 10% to 20% higher than what had been budgeted," says certified financial planner Debra Morrison, of Trovena's Roseland, N.J., office. Even if you stay put, you'll have free time to fill, and activities, such as golf or fixing up the house, cost money, too. "We tell clients that the 'common wisdom' that retirees spend 75% of what working people do is a dangerous thing to believe. We do goal setting to discover how they actually picture their retirement, and then try to place a price tag on it," says certified financial planner Barry Kaplan, of Cambridge Southern Financial Advisors, in Atlanta.

Those first few years in particular may be expensive as you enjoy your freedom from work, so budget accordingly when drawing up your retirement income plan. "Retirees desire to travel and become more active in the lives of their children and grandchildren," says certified financial planner Lazetta Rainey Braxton, of Financial Fountains, in Chicago. "It's hard to plan for activities and 'unassigned gifting' when a retiree has never set aside these 'line items' in their budget."

Higher Spending

Most people realize that they are paying a tax into the Social Security system during their working years, but did you know that you may also have to pay tax on your benefits once you start receiving them? Up to 85% of Social Security benefits are taxable, and the income thresholds that trigger Social Security income taxation are low -- $32,000 for a married couple, for example (see Plan to Pay Taxes on Social Security). "Retirees have a difficult time adjusting to the taxability of Social Security income and the low income thresholds. Most retirees don't see Social Security as taxable deferred income since they paid into the government fund using after-taxed dollars during their employment years. In their minds, retirement income shouldn't be taxed twice," says certified financial planner Lazetta Rainey Braxton, of Financial Fountains, in Chicago.

You'll also forfeit some benefits if you continue to work before you hit full retirement age -- you give up $1 in benefits for every $2 you make over the annual earnings limit (for 2013, that limit is $15,120). The good news is that once you pass full retirement age, your benefit will be adjusted upward to account for the forfeited benefits. To learn more about the ins and outs of Social Security, check out our Special Report: Maximizing Social Security Benefits.

Social Security Taxes

Uncle Sam not only wants a piece of your Social Security benefits, but he's ready for his slice of your pretax retirement savings. When you withdraw money from a traditional IRA or 401(k), those dollars stashed away pretax have a tax bill attached to them when they come out of the account, says certified financial planner Burt Hutchinson, of Fisher & Hutchinson Wealth Advisors, which has offices in Wilmington and Lewes, Delaware. Money you pull from tax-deferred retirement accounts is taxed at your top ordinary-income tax rate. So if you need $30,000 to buy a new car and you are in the 25% tax bracket, you'll need to withdraw $40,000 from your IRA to cover the cost of the car and the $10,000 tax bill on the withdrawal.

You can leave the money in tax-deferred retirement accounts until you hit 70 1/2. Starting at that age, seniors are required to take minimum withdrawals from IRAs and 401(k)s. If you have a large amount of money in those accounts, a sizable RMD may push you into a higher tax bracket than you thought you'd end up in upon retirement. To mitigate the tax hit, it could be advantageous to tap those accounts sooner than later. Another smart strategy: Start stashing money in a Roth IRA, which has no RMDs for account owners and can be tapped tax-free. Learn more about the retirement tax trap by reading Prepare for the Retirement Tax Bite.

Taxes on Nest-Egg Withdrawals

Estate planning is critical to make sure your assets are passed down as you wish. But another critical component of estate planning for couples is making sure that the surviving spouse will have enough money to live on. "One thing people don't plan for is the reduction of income if a spouse or partner dies -- without corresponding reduction in expenses," says certified financial planner Kathy Hankard, of Fiscal Fitness, in Verona, Wis. For example, if both spouses are both receiving Social Security benefits, a significant chunk of that income stream will disappear.

The surviving spouse can switch to a survivor benefit if that is higher than her own, but the survivor benefit will not make up for the lost income of going from two benefits down to one. This is one reason why boosting the potential survivor benefit through delayed retirement credits is a smart strategy for couples. The higher-earning spouse can wait to take his benefit, which can earn up to 8% a year in delayed credits up to age 70, and at that spouse's death, the survivor can switch to a benefit worth 100% of the deceased spouse's benefit, including the delayed credits plus cost-of-living adjustments (see Make the Right Moves to Boost Benefits).

The same income reduction can happen if a spouse who receives a pension hasn't signed up for a joint-and-survivor annuity. If the annuity is only based on his life expectancy, at his death, that income source will dry up with no payments for the surviving wife. Choosing the joint-and-survivor option may result in less money monthly, but it will provide income for the surviving spouse if the pensioner dies first. Learn more about pension payout options by reading Pension Quandary: Lump Sum or Annuity?.

Plan ahead to ensure that your spouse will have enough money to maintain his or her standard of living. Read A To-Do List for the Surviving Spouse to help prepare.

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