If you're like 40% of Americans, you're making one extremely common financial mistake... and it could be costing you way more than you think.

All told, some experts think this single thing could cost most people over $500,000 over their lifetimes. For some, it could be a million-dollar mistake.

Most people aren’t intentionally doing it, but through a series of other money mishaps wind up unable to do the single most important thing when it comes to long-term wealth -- investing early. In this video from our YouTube channel, our team breaks down the huge difference between getting started in your 20s, 30s, and 40s, and some of the other most common money mistakes people make.