Investing in mutual funds for retirement is never too late. And the Zacks Mutual Fund Rank can be an excellent tool for investors looking to invest in the best funds.

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 learn about some of Zacks' highest ranked mutual funds with low fees you may want to consider.

Hennessy Cornerstone Mid Cap 30 Investor (HFMDX Quick QuoteHFMDX - Free Report) has a 1.36% expense ratio and 0.74% management fee. HFMDX is a Mid Cap Blend mutual fund that typically features a portfolio filled with stocks of various sizes and styles; it allows for a diversification strategy focusing on companies with market caps between $2 billion and $10 billion. With yearly returns of 12.87% over the last five years, this fund clearly wins.

JPMorgan Intrepid Growth Fund R5 (JGIRX Quick QuoteJGIRX - Free Report) . Expense ratio: 0.44%. Management fee: 0.3%. JGIRX 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 10.42% over the last five years.

Fidelity Select Software & IT Services (FSCSX Quick QuoteFSCSX - Free Report) is an attractive large-cap allocation. FSCSX is a Sector - Tech mutual fund, allowing investors to own a stake in a notoriously volatile sector with a much more diversified approach. FSCSX has an expense ratio of 0.69%, management fee of 0.53%, and annual returns of 12.84% 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.