Schwab Retirement Plan Services Inc.,which provides companies with 401(k) plans for about 1.3 million workers, announced today that it is launching a full-service 401(k) program with low-cost index exchange-traded funds.

The company, an affiliate of Charles Schwab Corporation, is marketing the plan directly to employers as well as retirement plan consultants. Several companies have expressed interest and could be offering the plan to their employees later this year, Schwab said.

The platform includes about 80 ETFs in 25 asset categories from 11 firms that include Charles Schwab Investment Management, ETF Securities, First Trust, Guggenheim Investments, Invesco PowerShares, iShares ETFs, Pimco, State Street Global Advisors, Van Eck Global, Vanguard and United States Commodity Funds. The platform is an ETF version of Schwab Index Advantage, an index mutual fund 401(k) retirement program launched in 2012.

“Using a patent-pending process, Schwab Index Advantage is the first 401(k) program that fully integrates exchange-traded funds as core investments within the plan, including commission-free intraday investing along with the ability to process partial share interests,” said Steve Anderson, head of Schwab Retirement Plan Services.

"Other 401(k) offerings that we’ve seen take a less comprehensive approach to including exchange-traded funds and also tend to serve smaller plans,” he added.

TD Ameritrade has made ETFs available as some of the investment options in their 401(k) platform since 2011. Last week, TD Ameritrade announced that it was upgrading its 401(k) platform for advisors.

As with the index mutual fund version of Schwab Index Advantage, the ETF version offers a managed account advisory service with ongoing investment management based on a variety of factors including an employee's age, income, account balance and savings rate in his or her 401(k) plan. The advisory services are provided by GuidedChoice Asset Management Inc. or Morningstar Associates.

However, workers who prefer to manage their account themselves can do so using either the ETFs provided under the plan or by opening a self-directed brokerage account if their employer offers this feature.

Assets in ETFs have grown from $66 billion in 2000 to more than $1.6 trillion at the end of 2013, says the Investment Company Institute.

"The extraordinary growth of exchange-traded fund assets is undeniable and reflects their ability to meet investor needs. The notion by some industry commentators that these benefits should not be available to 401(k) participants reminds me of the proponents of gas lighting who, 100 years ago, argued that electricity was dangerous and unnecessary,” says Anderson.