Regardless of your age now, it will only get harder to accumulate a million dollars if you put off saving for another year. "Assuming retirement at age 65 and a 7% return, an investor who starts saving at age 25 has to save about $420 per month to reach that million-dollar milestone, while a person who waits until age 35 to start saving has to save double that, about $885 per month," says Matt Hylland, investment advisor at Hylland Capital Management, in Norfolk, Va.