The Houston Firefighters’ Relief and Retirement Fund (HFRRF) made news recently when it announced it was investing $25 million in bitcoin and ether, marking what was believed to be the first time a U.S. pension fund had put cryptocurrencies directly on its balance sheet.

Of course, $25 million is only a drop in the bucket compared to the $5.5 billion in total assets held by the fund – more precisely, it represents just 0.5% of its portfolio. But it still was a notable first step by the historically conservative investment fund. And if other pension and retirement funds follow suit, it could open up a huge source of additional demand for cryptocurrencies, with the funds collectively controlling trillions of dollars in global assets.

To be sure, the HFRRF was not the first U.S. pension fund to invest in crypto more broadly. That distinction appears to belong to the Fairfax County Police Officers Retirement System and Fairfax County Employees’ Retirement System, which in 2018 began investing in funds managed by Morgan Creek Digital that would eventually add up to a combined $73 million. The Morgan Creek funds leaned more toward blockchain technology than bitcoin, however, so the pension funds considered the moves venture capital investments.

In September, news broke that the pension funds, which manage a combined $7.2 billion in assets, were planning to make a $50 million investment in Parataxis Capital Management’s main fund, which buys digital tokens and cryptocurrency derivatives. The investment has since been approved by the funds’ board.

Asked if the funds are considering further crypto investments and whether direct investments were on the table, Katherine Molnar, chief investment officer for the police officers retirement fund, said her organization is “considering further investments in the crypto/digital assets space.”

“We have not made a final decision as to what form that might take. We remain constructive on the expected growth of this area,” Molnar told CoinDesk in an email.

Last week, Bank of America weighed in on pension investments in cryptocurrencies in a digital assets-focused research note.

“Our discussions suggest that many pension funds are still in the exploratory stage. State pension funds in the U.S. are significantly underfunded with ~$1.25 [trillion] in unfunded liabilities as of the end of FY19, which has led many to attempt to make up the shortfall between plan assets and obligations through investments. Pension funds globally held $35 [trillion] in AUM [assets under management] at the end of 2020, illustrating the potential tailwinds for digital assets if more pension funds begin to add exposure,” wrote analysts Alkesh Shah and Andrew Moss.

BofA referenced the HFRRF and Fairfax pension fund investments and noted that Queensland Investment Corporation, Australia’s fifth-largest pension fund, has expressed interest in cryptocurrency investments.

On the other hand, pension funds in South Africa could be prohibited from investing in cryptocurrencies under a rule change proposal published last week. Other overseas pension investments also face potential limitations on their ability to invest in crypto.

In the U.K., for example, pension funds hire specialized investment managers to invest on their behalf, with fund trustees unable to participate in the day-to-day management of the fund, Kerrin Rosenberg, CEO of U.K.-based pension management firm Cardano Investment, which is unrelated to the blockchain, told CoinDesk.

“I am not aware of any U.K. pensions actually considering a strategic allocation to cryptocurrency as an asset class. I would expect that most of the asset allocation models used by consultants don’t cover cryptocurrency, and, if asked, the consultants would probably argue,” Rosenberg wrote in an email.

“However, cryptocurrency investment could be made on a more tactical basis by investment managers as part of a wider mandate,” Rosenberg added.

James Stickland, CEO of London-based digital asset trading infrastructure developer Elwood Technologies, was also skeptical that the U.S. pension investment trend would make it to the U.K.

“In the U.K., we’re seeing rising institutional demand from banks, hedge funds, private companies and even family offices. Yet, it is unprecedented to see pension funds weighting even a small percentage of their portfolios to risk assets like bitcoin. I don’t think we will see them following the lead of pension funds in the U.S. anytime soon, but it’s certainly possible if inflation continues to be a concern,” Stickland said via email.