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 break down some of the mutual funds with the top Zacks Mutual Fund Rank and the lowest fees.

JPMorgan Large Cap Growth R2

(JLGZX): 1.19% expense ratio and 0.45% management fee. JLGZX 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. With annual returns of 20.11% over the last five years, this fund is a winner.

T. Rowe Price Diversified Mid-Cap Growth

(PRDMX): 0.85% expense ratio and 0.64% management fee. PRDMX is a Mid Cap Growth mutual fund. These funds aim to target companies with a market capitalization between $2 billion and $10 billion that are also expected to exhibit more extensive growth opportunities for investors than their peers. PRDMX, with annual returns of 11.22% over the last five years, is a well-diversified fund with a long track record of success.

Pzena Emerging Markets Value Inv

(PZVEX). Expense ratio: 1.43%. Management fee: 1%. Five year annual return: 8.8%. PZVEX is a part of the Non US - Equity fund category, many of which will focus across all cap levels, and will typically allocate their investments between emerging and developed markets.

We hope that your investment advisor (if you use one) has you invested in one or all of the top-ranked mutual funds we've reviewed. But if that isn't the case, it might be time to have a conversation or reconsider this vitally important relationship.

Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report

Get Your Free (JLGZX): Fund Analysis Report

Get Your Free (PRDMX): Fund Analysis Report

Get Your Free (PZVEX): Fund Analysis Report

To read this article on Zacks.com click here.

Zacks Investment Research