Young people have high hopes for their financial futures: 53 percent of millennials (defined here as those aged 21 to 37) expect to become millionaires at some point in their lives, if they aren't already, according to a recent survey from TD Ameritrade.

But to reach that goal, they need to sock away some serious cash. So, how much are millennials actually saving each month?

LendEDU, which surveyed 1,000 Americans between the ages of 22 and 37, found that millennials put an average of $480 per month into retirement savings. That means they're off to a strong start: Compounded over 40 years with an annual rate of return of 6 percent, that could add up to about $900,000.

However, not all young people are prioritizing the future. Though on average, millennials put more money per month towards long-term savings than they spend on restaurants or lattes, the survey reports that 49 percent spend more on dining out per month than they put towards retirement, and 27 percent spend more just on coffee.