Fidelity Investments cut fees for the majority of its college savings plans as it launched portfolios that combine active and passive money management.

The lower fees on 15 of 22 plans will save investors more than $4 million a year, Fidelity said Tuesday in a statement. The Boston-based company, which manages $25 billion of the so-called 529 savings plans sponsored by the states of Arizona, Delaware, Massachusetts and New Hampshire, also said that on Oct. 3 it launched eight new college saving portfolios that combine active and index investments.

The latest move is part of an ongoing fee changes at closely-held Fidelity, which has $2.8 trillion under management. The company has in the past several years joined the asset management price wars with Charles Schwab Corp., Vanguard Group and BlackRock Inc., all of whom have reduced fees on index mutual funds and ETFs.

Fidelity, which built an empire on the prowess of its stock pickers, startled the industry last year by offering several zero-fee index mutual funds and has since expanded its slate of commission-free ETFs, giving investors more options with smart beta and active products.

This article provided by Bloomberg News.