Money Market Funds Guide UK — Low-Risk Investing Explained
How money market funds work in the UK, typical returns, risks, tax treatment, and how they compare to savings accounts, cash ISAs, and other low-risk options.
·3 min read
Money market funds are a popular way to earn interest on cash while keeping risk extremely low. Here’s how they work.
What Is a Money Market Fund?
Feature
Detail
Definition
Investment fund holding very short-term, low-risk debt
What it holds
Treasury bills, certificates of deposit, commercial paper, short-term bonds
Goal
Return close to the Bank of England base rate with high stability
Risk level
Very low — but not FSCS protected
Access
Same day or next day in most cases
Minimum investment
Typically £1–£100 on platforms
Typical yield
4.0–4.5% (gross, in a 4.5% base rate environment)
How They Work
Step
Detail
1
You invest money into the fund (via a platform or broker)
2
The fund manager pools money from all investors
3
Invests in short-term, high-quality debt instruments
4
Interest earned is passed to you as distributions (income units) or reinvested (accumulation units)
5
You can withdraw at any time (same day or T+1)
Popular UK Money Market Funds
Fund
OCF
Yield (approx.)
Min investment
Royal London Short Term Money Market
0.10%
~4.3%
£1 (via platform)
L&G Cash Trust
0.11%
~4.2%
£1
Vanguard Sterling Short-Term Money Market
0.12%
~4.3%
£100
Aberdeen Standard Liquidity Fund
0.10%
~4.3%
£1
BlackRock ICS Sterling Liquidity
0.10%
~4.3%
£1
Fidelity Cash Fund
0.15%
~4.1%
£1
HSBC Sterling Liquidity
0.10%
~4.2%
£1
Yields are illustrative and fluctuate with interest rates. OCF = Ongoing Charges Figure.
Money Market Funds vs Savings Accounts
Factor
Money market fund
Easy-access savings account
Typical return
4.0–4.5%
3.5–5.0% (best rates)
FSCS protection
No
Yes (up to £85,000)
Access
Same day / T+1
Instant
Risk
Very low (but not zero)
Zero (within FSCS limit)
Can hold in ISA
Yes
Yes (Cash ISA)
Can hold in SIPP
Yes
No (most SIPPs don’t offer deposit accounts)
Platform fee
0.1–0.45% of your balance
None
Rate changes
Tracks base rate closely
Bank can (and does) change rate without notice
Switching
Instant on same platform
May need to open a new account
When Money Market Funds Make Sense
Situation
Why
Cash within an investment platform
Earn interest on uninvested cash alongside your stocks and shares ISA/SIPP
Emergency fund within an ISA
Keeps the ISA tax wrapper while earning near-base-rate returns
Large sums over £85,000
Savings accounts are only FSCS-protected up to £85k — MMFs diversify across many institutions
Parking cash before investing
While you decide what to invest in
Corporate treasury management
Businesses parking cash reserves
When a Savings Account Is Better
Situation
Why
You want FSCS protection
Bank deposits are protected up to £85k
Small amounts (under £85k)
Savings account is simpler and protected
Not using an investment platform
Saves on platform fees
You want the best headline rate
Top savings accounts can beat MMFs by 0.2–0.5%
You want zero risk
MMFs can theoretically lose value (though extremely unlikely)