It is never too late to invest in mutual funds for retirement. As such, if you plan to invest in some of the best funds, the Zacks Mutual Fund Rank can provide you with valuable guidance.

How can you tell a good mutual fund from a bad one? It's pretty basic: if the fund is diversified, has low fees, and shows strong performance, it's a keeper. Of course, there's a wide range, but using the Zacks Mutual Fund Rank, we've found three mutual funds that would be great additions to any long-term retirement investors' portfolios.

Let's take a look at some of our top-ranked mutual funds with the lowest fees.

If you are looking to diversify your portfolio, consider Fidelity Advisor Technology M (FATEX Quick QuoteFATEX - Free Report) . With a much more diversified approach, FATEX--part of the Sector - Tech mutual fund category--gives investors a way to own a stake in the notoriously risky tech sector. This fund is a winner, boasting an expense ratio of 1.21%, management fee of 0.53%, and a five-year annualized return track record of 25.32%.

JPMorgan Intrepid Growth Fund A (JIGAX Quick QuoteJIGAX - Free Report) . Expense ratio: 0.84%. Management fee: 0.3%. JIGAX is a Large Cap Growth mutual fund, and these funds invest in many large U.S. firms that are projected to grow at a faster rate than their large-cap peers. This fund has managed to produce a robust 17.92% over the last five years.

TCM Small Cap Growth Fund (TCMSX Quick QuoteTCMSX - Free Report) is an attractive large-cap allocation. TCMSX is a Small Cap Growth mutual fund and tends to feature small companies in up-and-coming industries and markets. TCMSX has an expense ratio of 0.91%, management fee of 0.8%, and annual returns of 10.45% over the past five years.

There you have it. If your financial advisor had you put your money into any of our top-ranked funds, then they've got you covered. If not, you may need to talk.