Five Things I Learned From 7 Years of APRA Banking Data

01Macquarie Is Quietly Eating the Big 4’s Lunch

Mar 2019 → Dec 2025

In March 2019, Macquarie held $9.9B in household deposits — a rounding error next to CBA’s $254B. By December 2025, that number was $101.1B. That’s +918% growth.

Their deposit market share went from 1.1% to 5.9%. Their housing loan share from 2.1% to 6.8%. Meanwhile, the Big 4’s combined asset share fell from 74.3% to 69.9%.

Macquarie’s strategy is straightforward: competitive rates, no branches, pure digital. They’ve effectively become Australia’s fifth pillar bank — and they did it in six years.

02COVID Created $154 Billion in “Excess” Deposits

Mar 2020 → Dec 2021

Before COVID, household deposits were growing at about 0.39% per month. When lockdowns hit, that more than doubled to 1.01%.

April 2020 saw $21.7B flow into household accounts in a single month — more than 5x the pre-COVID monthly norm. July 2020 was even bigger: $30.7B.

By December 2021, Australian households held $154B more in deposits than the pre-COVID trend would have predicted. That’s stimulus payments, JobKeeper, and nowhere to spend money during lockdowns, all compounding at once.

And it didn’t normalize quickly. Even in 2025, July months still show outsized $30B+ deposit spikes — likely driven by EOFY tax returns and super contributions flowing through the system.

03Investment Lending Never Recovered

2019 → 2025

In March 2019, investment loans made up 38.0% of all housing lending. By December 2025, that had fallen to 32.3%.

Two of the Big 4 actually shrank their investment books in absolute terms:

This is the long tail of APRA’s 2014–2017 macro-prudential interventions: investor lending caps, interest-only lending restrictions, and the Royal Commission’s scrutiny all made banks cautious about the investor segment.

Owner-occupied lending, meanwhile, grew +55% over the same period. The regulators permanently shifted the composition of Australian housing credit.

04Banks Became Deposit-Funded (and Stayed That Way)

System-wide deposit/loan ratio

The system-wide deposit-to-loan ratio jumped from 74% in March 2019 to 85% by late 2025.

Before COVID, Australian banks relied heavily on wholesale funding markets (bond issuance, securitization, offshore borrowing) to fill the gap between deposits and loans. The pandemic deposit surge, combined with the RBA’s Term Funding Facility, fundamentally changed the equation.

The Big 4 saw the biggest shift — they were more reliant on wholesale markets and had the most to gain. This is structurally positive: deposit funding is stickier, cheaper, and makes the banking system more resilient to global credit market disruptions.

05The Market Is (Slightly) Less Concentrated

HHI & market share trends

The HHI (Herfindahl-Hirschman Index) for total assets fell from 1,438 to ~1,300. Not a revolution, but a consistent trend — the market is slowly deconcentrating.

The Big 4’s share of total assets dropped 4.4 percentage points. But the “Big 5” share (including Macquarie) only dropped from 77.4% to 75.0% — meaning Macquarie absorbed a lot of the share the Big 4 lost.

Beyond Macquarie, the other gainers were mid-tier challengers:

Meanwhile, ING — once the poster child for digital banking in Australia — saw its deposit share slip from 3.65% to 3.21%. Macquarie ate their moat.