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.

The easiest, most reliable way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. The Zacks Mutual Fund Rank, which covers over 19,000 mutual funds, has helped us identify three outstanding options that are perfect for any long-term investors' portfolios that is retirement-focused.

Here are the funds that have achieved the Zacks Mutual Fund Rank #1 (Strong Buy) and have low fees.

If you are looking to diversify your portfolio, consider American Beacon Large Cap Value Institutional (AADEX). AADEX is a part of the Large Cap Value category, and invests in equities with a market capitalization of $10 billion or more, but whose share prices do not reflect their intrinsic value. This fund is a winner, boasting an expense ratio of 0.65%, management fee of 0.55%, and a five-year annualized return track record of 16%.

Putnam Small Cap Value R (PSCRX): 1.39% expense ratio and 0.61% management fee. PSCRX is a Small Cap Value mutual fund option, which typically invest in companies with market caps under $2 billion. With yearly returns of 15.97% over the last five years, PSCRX is an effectively diversified fund with a long reputation of solidly positive performance.

William Blair Small Cap Growth N (WBSNX) is an attractive large-cap allocation. WBSNX is one of many Small Cap Growth mutual funds; these funds tend to create their portfolios around stocks with market capitalization of less than $2 billion. WBSNX has an expense ratio of 1.24%, management fee of 0.94%, and annual returns of 10.52% 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.

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This article originally published on Zacks Investment Research (zacks.com).

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