When you're in your 50s or 60s and retirement starts drawing near, it's natural to focus your efforts on saving for your golden years. Mustering up that same motivation in your 20s and 30s, on the other hand, is easier said than done, especially when retirement seems like a far-off milestone, you're not at your peak earning capacity, and you have other pressing expenses (think mortgage payments and student loans) to worry about.

The problem, though, is that if you put off retirement savings for too long, you risk falling short when your golden years eventually roll around. Such is the predicament many millennials are in today, according to data from Provision Living. That's because 43% of younger adults have less than $5,000 saved for the future, and if they don't start ramping up, they're going to have a hard time enjoying their lives down the road.

Woman at laptop with worried expression

IMAGE SOURCE: GETTY IMAGES.

You need retirement savings

Let's be clear: No matter how modest a lifestyle you expect to lead in retirement, your senior years aren't going to fund themselves. If we're lucky, Social Security will still be as alive and kicking as it is today, which means you'll get some income in the form of monthly benefits. Those benefits, though, in a best-case scenario, will most likely only be enough to replace about 40% of your pre-retirement income. And that's a problem, because most seniors today need roughly twice that amount to pay the bills and live comfortably. And unless you're in the minority of younger workers who happen to have access to an employer pension, you'll need serious savings to cover that gap.

If there's one thing you have going for you as a millennial, it's time, and if you take steps to improve your savings today, there's a good chance you'll amass more than enough of a nest egg to live the retirement lifestyle you want. Let's imagine you're 35 years old with absolutely no money in long-term savings -- not a great place to be financially. Here's what you stand to retire with if you start making an effort to do better immediately:

Monthly Savings Amount Over the Next 30 Years:

Ending Retirement Plan Balance at Age 65 (Assumes a 7% Average Annual Return on Investment):

$200

$227,000

$300

$340,000

$400

$453,000

$500

$567,000

$600

$680,000

$700

$793,000

$800

$907,000

$900

$1.02 million

$1,000

$1.13 million

TABLE AND CALCULATIONS BY AUTHOR.

As you can see, retirement is by no means a lost cause, even if you've spent the first decade or so of your career neglecting your savings completely. By the same token, the more you're able to save from this point forward, the more financial security you'll buy yourself during your senior years.

Of course, saving a substantial amount of money month after month is easier said than done, but if you're willing to make lifestyle changes, it's certainly doable. So, take a look at your current budget, or create one if you don't yet have one in place, and find ways to start cutting back. That could mean downsizing to a cheaper living space, giving up a vehicle if there's public transportation where you live, or cooking more meals at home to save money on food.

On top of that, pledge to bank all of your raises and bonuses going forward to fuel your savings efforts. If you arrange to have each pay increase you get automatically land in your 401(k), you won't miss that money or be tempted to spend it, and it'll go a long way toward helping you accumulate wealth.

Finally, you might consider getting a side hustle if, after cutting expenses, you're not catching up on retirement savings as much as you'd like. Of the millions of Americans who are currently holding down a second gig, 14% do so for the express purpose of building a nest egg. Taking on an additional job might also allow you to make headway on your savings without having to give up too many of the luxuries you've come to enjoy.

Even if you're fairly young, it's never too early to start thinking about retirement. And the sooner you start building savings, the more options you'll buy yourself later in life.

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