Retirement should be a time to kick back and enjoy life, but planning for your golden years can be a major source of stress as you figure out how to support yourself for decades with no paychecks coming in.

As you make your savings plans to cover costs of living after you're no longer a worker on the payroll, it's important to have accurate information in order to make fully informed choices. Unfortunately, far too many people believe retirement myths -- which can leave them far short of having enough money saved. Here are three big retirement myths you should definitely learn the truth about long before it's time for you to hand in your final notice and give up the working world forever. 

Retired couple talking with another person

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1. Social Security is enough to live on

Not worried about saving for retirement because you're planning to live on Social Security? Unfortunately, this is definitely not a viable plan. The amount you'll bring home in Social Security varies depending upon how much you paid into the system and the age of your retirement. Average payments range from $1,046 if you retire at 62 to $1,268 if you retire at 70.  Even in a best case scenario, that means your household income would be just $15,216 per year, if you earn the average after retiring at 70. 

For a household of one person, the poverty level in 2017 is $12,060 -- so you'd have a few thousand dollars more than the minimum needed to survive if you were able to hang on at work long enough to earn the max. Unfortunately, age-related infirmity, illness, or inability to find a job force many people out of the workforce well before age 70. The average retirement age in the U.S. in 2015 was 63 ; if you retire at this age with an average Social Security benefit, your annual income would be just $12,996 -- pretty much right at poverty level. 

Unfortunately, having an income just above poverty level can actually make your life more difficult because these thresholds are often the cut-off for being eligible for various types of government assistance. You'll have just enough income to barely get by -- if you don't experience costly health issues or incur other unexpected costs like supporting a grandchild  -- but you'll earn too much to get benefits that could help.  

Bottom line: You cannot rely on Social Security, which is why it is important to invest for retirement so you'll have a nest egg to produce additional income.

2. Medicare will take care of all your healthcare needs

Myths about the Medicare program abound, with many young people believing that all their health needs will be covered once they turn 65 and qualify for Medicaid. Sadly, this is very far from reality. There are significant limitations on what Medicare will cover -- the program pays nothing for vision care, hearing aides, dental insurance, long-term care costs, or routine foot care. There are premiums that must be paid if you want supplementary Medicaid policies like a Medigap plan, and there are co-pay and co-insurance costs for hospital services and other healthcare services. 

The limitations on Medicare and gaps in coverage -- even for seniors with supplementary plans -- are so significant that studies estimate seniors will need to have $350,000 saved just for healthcare costs alone. If you are counting on Medicare and not making a plan to pay for care costs as a senior, such as investing in a Health Savings Account or putting aside extra money earmarked for your medical spending, you are likely to face serious financial trouble when you have retired. 

3. You won't spend as much once you're retired

Conventional wisdom says you need to replace about 70% to 80% of your pre-retirement income once you're no longer in the workforce .  Relying on this common advice could leave you with way less money than you actually need.  

Recent data from the Employee Benefit Research Institute revealed close to half of all families spend more once they've retired, not less. Close to a third of these retired families are spending way more, boosting their outflow by 120%. This extra spending isn't just coming from taking trips around the world. Many seniors face unavoidable high costs -- healthcare again -- and more seniors than ever are retiring with debts they still need to pay.  If you've based your retirement savings target on a plan to spend less than you were spending before and you instead spend more, you're going to run out of savings and be in dire financial straits. 

Rather than risk running out of cash, base your goals on replacing at least 100% of your income -- and a worst-case scenario associated with healthcare expenditures.  This means if you're earning $50,000 now, will retire in 20 years, will earn the average Social Security benefit and want to replace 100% of your income, you'd need a nest egg of around $1.2 million to replace your income-- and an additional $350,000 for healthcare for a total savings goal of $1.5 million -- assuming you earn 8% on your investments and keep around 50% of your portfolio invested in stocks as a senior .  

If you failed to take healthcare into account and planned only to replace 70% of your income, you might set your goal much lower at around $720,000 -- around half of what you'd actually need. Don't make this mistake. Be aggressive in setting goals for yourself. If you end up with too much money, you can live it up or leave a lot to your children. 

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