iShares Core Cash ETF (BILL) — Review & Analysis

BILL is the cheapest cash ETF on the ASX at 0.07% p.a. — less than half AAA's 0.18% fee and a fraction of MQIO's 0.49%. The fund tracks the Bloomberg AusBond Bank Bill Index, holding short-dated bank bills and other money market securities. AUM is $1.18 billion as at May 2026 — the third-largest fund on this page. Compare BILL across the full cohort on our high interest cash ETF page.

BILL's benchmark exposure differs slightly from AAA's pure-deposit structure. Bank bills are short-dated negotiable instruments (typically 30-180 day maturities) issued by Australian banks; they trade close to the RBA cash rate but introduce minor duration risk (typically 30-90 days). In practice the yield and behaviour are nearly identical to a pure deposit ETF, but the structure means BILL has marginally more sensitivity to changes in short-end rates between RBA meetings.

The fee advantage matters meaningfully for capital deployed at scale. On a $500,000 cash allocation, the 11bp gap between BILL and AAA saves $550 per year — meaningful when the underlying yield is 4-5%. The cheaper alternatives ISEC (0.12%, iShares' enhanced cash sibling) layer in a small amount of credit for additional yield; BILL stays cleaner on duration and credit by sticking to bank bills.

For investors prioritising the lowest possible cost in their cash sleeve — particularly large SMSFs, family offices and corporate treasuries — BILL is the natural starting point. The iShares (BlackRock) brand also provides institutional credibility that drives adviser and platform allocations. Our best cash ETFs guide covers all six cash options on yield, fees and structure.