In a recent column, I asked you to complete a retirement checklist to create a big-picture strategy. The next step is determining your needs. You may find that your needs and your actual savings don't come together in a nice package. In that case, knowing there is a gap will help you better prepare.

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Since there are so many variables, turning your needs into your savings number can be complicated. There are online calculators, and retirement planning professionals should be able to help. Some things to consider as you work toward your number are:

Lifestyle. Do you plan to maintain your current lifestyle? Retire more frugally? Take on new expenses? Oftentimes, financial advisers figure monthly retirement needs in terms of current monthly income. However, your income replacement need could be 70 percent or 105 percent of your current income.

Long-term care. Do you have long-term care insurance? If not, decide whether to budget for long-term care.

Retirement age. Earlier retirement means fewer earning years and more spending years.

Living situation. If you plan to live in a home with a paid-off mortgage, budget for home repairs, updates, and insurance. Renters, ensure your budget includes monthly rental payments forevermore.

Transportation. If you'll own a car, you'll need to pay for gas, upkeep, and insurance--and you may want to purchase new cars periodically during retirement.

Gifting. Do you plan to give your children monetary gifts?

Employment. Do you plan to work as a consultant or start a new business? Maybe you'd like to have a part-time job during retirement. Account for any income you plan to have.

Inflation. The average inflation rate has historically been about 3.4 percent per year.

Health care. Your retirement age and employment situation will alter your health insurance options. Even if you'll immediately qualify for Medicare, you'll still need money to pay for care within that program as it currently stands.

Post-retirement investing philosophy. Think about your risk tolerance during retirement. Your post-retirement investing plan may revolve around wealth preservation, or you may prefer to put your money to work, investing some portion in asset classes with more risk.

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Social Security. Under the current structure of Social Security, how much income do you anticipate receiving? Do you believe Social Security will pay at that rate when the time comes? There are differing opinions about the future of Social Security. To be safe, some retirement planners assume they'll receive no Social Security income.

Spousal/partner income. Remember to account for your spouse or partner's employer-sponsored retirement plan or IRA income.

Other income. Don't forget pensions, annuities, inheritance, and other investments. Consider when you'll receive them and in what form.

Filling in the gap

Once you determine how much money you'll likely need to live the retirement lifestyle you prefer, calculate how much money you're currently on track to have at retirement. This number is based on your current and future rate of saving with your ongoing investing style. Remember that it's wise to gradually move toward a more conservative allocation as you near retirement.

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If your goal is higher than your actual expected savings, you have a gap.

There are online gap analysis tools to help, but filling the gap means making financial changes. If you're on track to earn less money that you'll need, you can:

--Save more money now. To increase your current retirement contributions, you may need to change your current lifestyle: Spend less so you can afford to contribute more, or earn more by changing your employment situation.

-- Change your investing strategy to be more aggressive. However, people who already have a suitable, well-planned investing strategy in place should not invest at an uncomfortably aggressive level.

--Postpone retirement in order to put more money into a retirement account and spend less money from that account.

--Change your retirement goals and expectations. If you're unwilling or unable to make enough changes to fill the gap between your expected retirement account balance and your desired retirement account balance, something has to give. You'll need to have a less expensive retirement. Perhaps you'll need to travel less and forgo financial gifts to your children. You could work during retirement and take up fewer hobbies. Many Boomers are choosing to work longer and retire later.

Everyone contributing to an employer-sponsored retirement plan has taken a step in the right direction. But anyone serious about retirement readiness has to dig into the numbers.

Scott Holsopple is the president and CEO of Smart401k, offering easy-to-use, cost-effective 401(k) advice and solutions for the everyday investor. His advice has been featured on various news outlets, including FOX Business, USA Today and The Wall Street Journal. Keep tabs on Scott on Twitter and Facebook.

Read more:
Saving for a Comfortable Retirement