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.

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.

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

MFS Blended Research Growth Eq R6 (BRWVX Quick QuoteBRWVX - Free Report) : 0.42% expense ratio and 0.4% management fee. BRWVX 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. BRWVX has achieved five-year annual returns of an astounding 15.14%.

Fidelity Convertible Securities (FCVSX Quick QuoteFCVSX - Free Report) : 0.74% expense ratio and 0.57% management fee. FCVSX is a Convertible Bonds mutual fund, and these funds are unique in the fixed income world; these securities have components of both fixed income and equity, making them hybrid securities. FCVSX, with annual returns of 10.43% over the last five years, is a well-diversified fund with a long track record of success.

JPMorgan Disciplined Equity A (JDEAX Quick QuoteJDEAX - Free Report) . Expense ratio: 0.6%. Management fee: 0.25%. Five year annual return: 14.14%. JDEAX is part of the Large Cap Blend section, and these mutual funds most often invest in firms with a market capitalization of $10 billion or more. By investing in bigger companies, these funds offer more stability, and are often well-suited for investors with a "buy and hold" mindset.

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.