One major benefit of saving in a 401(k) over an IRA is getting an opportunity to snag free money in the form of an employer match. It's estimated that 92% of companies that sponsor a 401(k) also offer matching contributions to varying degrees, and if yours does the same, you have a real opportunity to boost your nest egg tremendously.

Last year, nearly two-thirds of 401(k) participants contributed enough money to get their full employer match, according to data from Vanguard. On the flip side, this means that roughly one-third of workers failed to capitalize on that match, and lost out on money as a result. And that's a mistake that they -- and you -- should not repeat.

At first glance, it may seem like forgoing an employer match isn't all that big a deal. Imagine your company is willing to match up to 3% of your salary, and you earn $50,000 a year. By giving up that match (which would happen if you were to fail to contribute 3% yourself), you'll lose out on $1,500, which, by itself, will hardly spell the difference between retiring comfortably or not. However, losing out on $1,500 year after year is a different story, and while it's one thing to forgo that match once (say, during a year when you have a series of unplanned bills and can't part with any amount of money), doing so throughout your career could seriously set you back.

Furthermore, anytime you give up an employer match, you also lose out on whatever growth that money can achieve. So let's imagine you pass up a $1,500 match at age 30 and retire at age 67. Meanwhile, your investments grow at an average rate of 7% a year during that time. What this means is that at the end of the day, you'll have lost out on over $18,000 when you take investment gains on that $1,500 into account. And that's a lot more serious.

Now let's take things one step further. Imagine that instead of giving up $1,500 one year, you give it up every year between age 30 and age 67. Assuming that same 7% return, you'll end up losing out on $240,000 after all is said and done. And that could spell the difference between retiring comfortably and coming up short during your golden years.

You might not manage to max out your 401(k) at any point during your career, or even get close, but what you should absolutely aim to do is contribute enough each year to snag your employer match. So if that's not your plan at present, change it. Unload some expenses to free up more cash in your budget, or get a side gig on top of your regular job and use its proceeds to fund your 401(k). Furthermore, always make a point of saving your raises, as well as any bonuses that come your way.

Giving up free money is a downright crazy thing to do -- so don't. Figure out how much you need to contribute to get your company match in full, and take steps to make that feasible. Last year, almost 66% of 401(k) participants got the total match they were entitled to, and if you play your cards right this year, you can do the same.