DBS, OCBC, and UOB account for the overwhelming majority of customer deposits, reflecting high market concentration.

Deposit Growth and Market Size

Singapore's banking sector has experienced sustained deposit growth, with total customer deposits reaching SGD 1.8 trillion by end-2023. In U.S. dollar terms, total deposits hit an all-time high of USD 1,628.6 billion in March 2026, up from USD 1,608.5 billion in February 2026, according to CEIC Data. This marks a record high in a data series dating back to January 1991, when total deposits stood at just USD 99.3 billion.

The growth trajectory reflects structural demand for Singapore as a safe haven for capital. Geopolitical uncertainty has been a key driver of foreign fund inflows into the Singapore banking system, according to Lion Global Investors' 2025 Singapore Market Outlook. The report notes that with uncertainty unlikely to abate, Singapore banks are expected to remain beneficiaries of this global trend. The deposit base has expanded steadily over the years, with Lion Global Investors' figure showing deposits increasing consistently across the period illustrated.

Concentration Among the Big Three

DBS, OCBC, and UOB held over SGD 1.2 trillion in customer deposits in 2025, representing approximately 85% of total domestic banking system deposits. This concentration is notably higher than their share of total banking assets, which stood at 70% in 2023. The disparity between deposit share and asset share underscores strong customer loyalty, deep retail and corporate relationships, and significant wholesale deposit inflows that favour the largest domestic institutions.

The big three's deposit dominance is a function of their extensive branch networks, trusted brand equity, and capture of high-net-worth and corporate cash flows. DBS, OCBC, and UOB also lead regional asset rankings across ASEAN, reinforcing Singapore's position as Southeast Asia's financial hub. Their combined deposit base gives them a structural funding advantage over foreign and smaller domestic competitors.

%Source: Orionmano Industries

Deposit Composition: Domestic vs. Foreign Currency

A distinguishing feature of Singapore's deposit base is its high proportion of foreign-currency deposits. As of end-2023, 60% of total customer deposits were denominated in foreign currencies, reflecting Singapore's role as an international financial centre and wealth management hub. Local-currency customer deposits stood at SGD 720 billion by end-2023.

This composition highlights the international nature of the banking system. Foreign-currency deposits are driven by corporate treasury operations, trade finance, and wealth management inflows from high-net-worth individuals across Asia and beyond. The Asian Currency Unit framework, which was historically used to capture foreign-currency transactions, is now integrated into the broader banking system, further supporting the large foreign-currency deposit share. The Monetary Authority of Singapore (MAS) collects total deposits in local currency and reports conversions to USD using period-end exchange rates, with the March 2026 all-time high reflecting both deposit growth and currency dynamics.

Implications for Financial Stability and Regulation

Despite the concentration of deposits among three institutions, Singapore's banking system remains one of the best-capitalised globally. The big three maintain strong capital adequacy ratios and liquidity buffers, mitigating immediate systemic risk concerns. Their diversified loan books, robust risk management frameworks, and regulatory oversight from MAS provide a foundation for stability.

MAS supervises 196 licensed banking institutions across seven licence types as of 2026, according to Easy Global Banking's comprehensive listing. These include three local banking groups, 30 full banks (domestic and foreign), 96 wholesale banks, and 27 representative offices, among other categories. The total assets of Singapore's banking sector have reached SGD 3.3 trillion, with over SGD 6 trillion in wealth under management. Digital transaction penetration stands at 95%.

However, deposit concentration raises legitimate financial stability considerations. A system where three banks hold 85% of deposits means that any operational or credit stress at one of these institutions could have disproportionate effects on the broader economy. MAS has addressed this through stringent supervisory requirements, including stress testing, capital surcharges for domestic systemically important banks (D-SIBs), and resolution planning frameworks. The regulator also operates the Singapore Deposit Insurance Corporation, which insures deposits up to SGD 100,000 per depositor per institution, providing a backstop for retail depositors.

Foreign banks maintain a 30% share of total assets, but their deposit share is significantly smaller, limiting their role in retail deposit gathering. Digital banks such as MariBank, which reports SGD 3.2 trillion in assets under management, are expanding but remain small relative to the traditional big three.

The outlook for the big three's deposit dominance remains favourable. Continued geopolitical uncertainty, capital inflows into Singapore as a financial hub, and the incumbents' corporate and retail relationships are likely to sustain their market share. Regulatory focus on concentration risk may intensify, but analysts expect any measures to focus on enhancing buffers and resolution capabilities rather than imposing structural caps on deposit share.