More workers may soon be able to stake some of their 401(k) retirement savings to Bitcoin, as cryptocurrencies crack even deeper into the mainstream.

Retirement giant Fidelity Investments Inc. has launched a way for employees to put some of their 401(k) savings and contributions — potentially up to 20 per cent — directly in Bitcoin, all from the account’s main menu of investment options. Fidelity said it’s the first in the industry to allow such investments without having to go through a separate brokerage window and it’s already signed up one employer that will add the offering to its plan later this year.

Fidelity’s offering may be one of just a few for a while, given the substantial concerns about the riskiness of cryptocurrencies. Last month, the U.S. government warned the retirement industry to exercise “extreme care” when doing something like this, highlighting how inexperienced investors may not appreciate just how volatile cryptocurrencies can be, among other concerns.

Read: Confidence in Bitcoin up among institutional investors: survey

Bitcoin had five days in the last year where it plunged by at least 10 per cent. The stocks in the S&P 500, meanwhile, had only two such drops in the last 50 years. Beyond its volatility, there’s still fundamental disagreement about how much a Bitcoin is worth or even if it’s worth anything at all.

Proponents say cryptocurrencies can boost returns in a well-diversified portfolio, without adding too much risk. That’s because cryptocurrencies haven’t always moved in the same direction as stocks and other investments, though they often have in recent months amid worries about rising interest rates.

Others in the industry are also working to offer similar products. ForUsAll announced a product in June 2021 to allow workers to put some of their 401(k) in cryptocurrencies by sending it to a self-directed window. The 401(k) provider plans to require savers to take an interactive quiz about the risks of cryptocurrencies before buying them, among other moves to educate investors. Fidelity also places  “digital speed bumps” in front of investors, forcing them to slow down and study the risks and rewards of crypto.

It may take a while for most employers to start offering something like this. The Plan Sponsor Council of America recently asked its members if the Labor Department’s warning changed their minds at all in terms of considering crypto. The majority (57 per cent) said they’d never consider crypto as a viable investment option regardless. Another third said the warning “simply affirms the concern we already had.”

Read: Dogecoin, NFTs taking centre stage while institutional investors wait in the wings