There is never a wrong time to invest in mutual funds for retirement. So, if you're still looking for the best mutual funds, the Zacks Mutual Fund Rank can be a great guide.

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.

Causeway Global Value Investor

(CGVVX): 1.1% expense ratio and 0.8% management fee. CGVVX is a Global - Equity mutual fund. These funds invest in large markets like the U.S., Europe, and Japan, and operate with very few geographical limitations. CGVVX has achieved five-year annual returns of an astounding 11.57%.

Columbia Dividend Income Fund Class I

(GSFTX). Expense ratio: 0.65%. Management fee: 0.53%. GSFTX is a Large Cap Value mutual fund, which invests in stocks with a market cap of $10 billion of more, but whose share prices do not reflect their intrinsic value. This fund has managed to produce a robust 11.53% over the last five years.

Janus Henderson Research N

(JRANX). Expense ratio: 0.51%. Management fee: 0.48%. Five year annual return: 16.37%. JRANX is a Large Cap Growth option; these mutual funds purchase stakes in numerous large U.S. companies that are expected to develop and grow at a faster rate than other large-cap stocks.

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.

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