Nearly 40% of Americans are losing sleep at night worrying about saving for retirement. Perhaps not coincidentally, this is almost identical to the percentage of Americans who have nothing saved for their senior years .  

Concerns about how you'll survive as a senior are not unfounded. There's a serious retirement crisis brewing, with median retirement-account balances throughout the U.S. valued at just $5,000, and studies showing we spend more time planning for vacations than for retirement. In fact, Americans may actually not be worried enough about retirement. 

If you're stashing away cash, you may be one of the millions of Americans who aren't concerned because you think you're covered -- but are you really? To take stock of your retirement situation, consider three red flags that suggest you're not saving enough. 

Calculator, glasses and money in an envelope labeled 401(k)

Image source: Getty Images.

1. You don't know how much you'll actually need to retire

More than 8 in 10 Americans don't know how much money they'll need to retire, and more than half of all Americans think they'll be OK with less than $1 million in savings. The reality: even $1 million may not be enough in costly cities where a seven-figure nest egg will barely last a decade.  

It's difficult to calculate exactly how much you'll need during retirement because there are lots of variables, like how long you'll live, and whether you'll have expensive health issues. But the bottom line is, if you don't have a goal, it's impossible to decide how much you need to save. 

To find your retirement number, follow this simple four step guide that involves determining what your budget will be as a senior, factoring in healthcare costs, and considering likely sources of income such as Social Security payments.

2. You aren't taking advantage of free money

Once you've got your retirement number, you may be dismayed how high it is. But don't despair -- your employer probably wants to help you retire, but it's up to you to take advantage of the assistance by investing enough to get a full 401(k) match. If your employer matches 401(k) contributions and you aren't getting every dollar of free cash, you're just costing yourself money that you could use down the road after you retire. 

Employer matches work differently at different companies, but the majority of companies offer some type of matching funds for 401(k) contributions, with the average coming in at around 2.7% of employee pay.

If you earn the median salary of $51,272, this would mean your employer would give you around $1,384 each year -- if your match was about average. This $1,384 would turn into $191,319 over 35 years of being invested in a 401(k) earning 7% returns. And this assumes you never got a raise. With regular raises and a slightly higher match, your employer's contribution to your 401(k) could be worth more than $520,000 over a 35-year career.

If you're saving so little you're foregoing free money that could turn into more than half a million dollars, it's time to find ways to increase your retirement savings. Start by spending less to increase 401(k) contributions -- at least enough to receive the maximum match. 

3. You're not increasing your contributions

Average employee contributions to 401(k)s have actually been on the decline. In 2015, employees deferred 6.9%, on average, and the median deferral rate was 6% of salary. In 2016, the average deferral rate was down to 6.2%, while the median deferral rate was 5%, according to Vanguard. 

The decline was driven, in part, by more employers auto-enrolling workers in 401(k) accounts with default contributions set at around 3%. Less than half of auto-enrolled accounts have automatic increases in contributions, and many employees stick with the default contribution rate, according to the Center for Retirement Research.

Whether you've been auto-enrolled, or have set your own 401(k) contributions, increase those contributions every year until you're saving enough to accomplish your goals. If you're not hitting the 401(k) contribution maximum of $18,500 for 2018, you'll likely be working up to the lesser of this maximum, or to savings between 15% to 20% of your income

Even a small annual increase makes a big difference. If you earned $51,272 and were contributing 5% of your salary, this chart shows how much more you'd have if you bumped up that contribution. The chart is based on starting to contribute at age 30, contributing for 35 years, getting a 2% raise each year, earning a 7% return on investments, and getting a 2.7% employer match throughout your career. 

Percent of Salary

Your Cumulative Contributions

Savings after 35 years

























Table source: Author.

Each percentage point increase in contributions on a $51,272 salary will cost you just over $40 per month -- less than the average cost of one meal out for a family of four. Isn't it worth the price of one dinner out to have $100,000 -- or more  -- in extra retirement funds? 

Make some quick fixes to have a secure retirement

It doesn't take a big sacrifice to make little changes that will leave you much more secure in retirement. Get out your calculator, find out what your goal is, then increase your contributions as quickly as you're able until you hit that number. When you're living it up as a senior instead of struggling to live on Social Security, you'll be really glad you made the effort.