Hargreaves Lansdown has launched the HL Money Market fund in collaboration with BNY Investments, responding to a 35% year-on-year rise in the number of clients holding money market funds.
The investment platform said the fund has an expected yield of 3.95% at launch and an ongoing charge of 0.06%. It said the charge is "the lowest ongoing charge in the UK retail market".
It is available exclusively to Hargreaves Lansdown clients, with same-day reinvestment and next-day withdrawals. BNY Investments will manage the fund's portfolio of short-term debt issued by governments, banks and companies with strong credit ratings.
Retail investment in money market funds reached a record £6.9bn across the market in 2025, with a further £3.8bn in the first half of 2026, according to the Investment Association.
Hargreaves Lansdown said an estimated £600bn is held in "excess cash" in the UK, much of it earning less than 1% in high-street savings accounts. The four biggest banks pay savers an average of 0.95%, according to the platform.
Only 31% of Cash ISA holders are aware of money market funds, IA research found. But 64% of Cash ISA holders and 81% of existing investors said they would consider investing once given a clear explanation.
Doug Abbott, chief product officer at Hargreaves Lansdown, said: "More than 25 times as many HL clients invest in money market funds as they did five years ago and they're set to become even more popular once the new Cash ISA rules come into force next April.
"Money market funds have long been a core cash management tool for institutions, which have historically had cheap, easy access. Through our collaboration with BNY Investments, we’ve opened up these benefits to our clients."
From April 2027, savers who have used their full £12,000 Cash ISA allowance will be able to hold money market funds within a Stocks and Shares ISA, under the new rules.
HL data also shows that one in five clients who open a Cash ISA go on to open an investment account within six months.