Each mutual fund charges its own expense ratio. In an ideal world, expense ratios would be as close to zero as possible. This way, you could keep more of your money. These funds do have expenses, though, so you should expect to pay a minimal expense ratio. Some funds charge expense ratios of almost 1%. You should avoid these funds unless their performance more than makes up for the expense ratio. Vanguard offers low-cost target-date funds — their expense ratio usually hovers around .10%. Vanguard also states the average expense ratio of similar funds generally falls at .60%.