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 best way to shortlist great mutual funds is to ensure solid performance, diversification, and low fees. Some are better than others, but utilizing the Zacks Mutual Fund Rank, we have identified three mutual funds that could be solid additions to one's retirement portfolio.

Let's take a look at some of our top-ranked mutual funds with the lowest fees.

Baird Midcap Institutional (BMDIX Quick QuoteBMDIX - Free Report) has a 0.81% expense ratio and 0.75% management fee. BMDIX is a Mid Cap Growth mutual fund. These mutual funds choose companies with a stock market valuation between $2 billion and $10 billion. With yearly returns of 11% over the last five years, this fund clearly wins.

Fidelity Convertible Securities (FCVSX Quick QuoteFCVSX - Free Report) is a stand out amongst its peers. 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. With five-year annualized performance of 11.26%, expense ratio of 0.73% and management fee of 0.51%, this diversified fund is an attractive buy with a strong history of performance.

Jensen Quality Growth Fund R (JENRX Quick QuoteJENRX - Free Report) is an attractive large-cap allocation. JENRX is a part of the Large Cap Growth mutual fund category, which invest in many large U.S. companies that are expected to grow much faster compared to other large-cap stocks. JENRX has an expense ratio of 1.26%, management fee of 0.48%, and annual returns of 11.03% over the past five years.

These examples highlight the fact that there are some astonishingly good mutual funds out there. If your advisor has you in the good ones, bravo! If not, you may need to have a talk.