Saving for retirement isn't something you can do overnight. The average worker estimates retirement will cost around $1.7 million, according to a survey from Charles Schwab, and it takes decades to accumulate that kind of cash.

However, around 42% of workers say they don't want to think about saving until they get closer to retirement age, a report from the Transamerica Center for Retirement Studies revealed. That could be a problem, because the longer you wait to start saving, the more difficult it becomes to catch up.

A man working at his laptop at a table in a coffee shop

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The key to retiring wealthy: Start saving early

The earlier in life you begin saving, the easier it is to build a robust retirement fund worth hundreds of thousands, or even over one million dollars. That's because compound interest allows your savings to grow exponentially the longer your money sits untouched in your retirement account.

Let's say, for example, you want to have $1.5 million saved by the time you turn 65 years old. Assuming you're earning a 7% annual rate of return on your investments, here's how much you'd need to save each month depending on the age you began saving:

Age You Began Saving Amount Saved per Month Total Savings by Age 65
20 $450 $1.543 million
25 $625 $1.497 million
30 $925 $1.534 million
35 $1,325 $1.502 million
40 $2,000 $1.518 million
45 $3,100 $1.525 million
50 $5,000 $1.508 million
55 $9,000 $1.492 million
60 $22,000 $1.518 million

Data source: Author's calculations.

While saving a few hundred dollars per month in your 20s or 30s may be challenging, it's far more feasible than stashing away thousands of dollars per month if you were to wait until your 40s or beyond to start saving.

What to do if you're off to a late start

If you're behind on your savings (or haven't started yet), all hope is not lost. While it's more difficult to save a significant amount of money when you're off to a late start, it's not impossible. And saving a little is better than saving nothing.

First, set a goal for yourself. Run your numbers through a retirement calculator to see how much you should have saved by retirement age, as well as what you should be setting aside each month to reach that target.

From there, you have a couple of options. Depending on how far behind you are on your savings, your monthly goal might be out of reach. One option is to make significant budget cuts to find as much extra cash as you can. You may even choose to take drastic measures, such as downsizing your home or selling your car. If you've made all the cuts you can, and it's still not enough, you may need to rethink your retirement expectations. You might delay retirement by a few years, for example, or consider moving to a less expensive city or neighborhood once you retire to save money.

Another option is to consider delaying Social Security benefits. You can begin claiming as early as age 62, but for every year you wait beyond that age (up to age 70), you'll receive 8% more in benefits. That could amount to hundreds of dollars more per month, which can go a long way if your personal savings aren't as strong as you'd hoped they would be.

Saving for retirement isn't easy, but if you're putting it off, you may inadvertently be making it harder for yourself. By getting started as early as you can, it will be easier to build a healthy retirement fund so you can enjoy your senior years comfortably.