Home bias is the tendency of investors to allocate disproportionately to domestic assets relative to what global market weights or portfolio theory would predict. It leaves households and institutions overweight their own economy, under-diversified against local shocks, and reluctant to fund cross-border investment and transitions.
How it works
Standard portfolio theory says investors should hold the global market portfolio, weighting each country by its share of world market capitalisation. Home bias is the gap between that benchmark and actual holdings: a US investor holding 80% domestic equities when the US is ~60% of world cap exhibits ~20 points of home bias. Drivers include information asymmetry, currency and hedging costs, transaction frictions, regulatory steering, and behavioural familiarity.
Why it matters now
In 2025-2026 home bias is central to Europe's Capital Markets Union debate: fragmented, domestically-anchored savings pools cannot efficiently finance pan-European firms or the energy and defence transitions, leaving the EU reliant on US capital markets despite high aggregate savings.
Example
Euro-area households hold roughly €35tn in financial assets, much of it in low-yielding domestic deposits and home-sovereign bonds rather than diversified pan-European or global equity. The European Commission's 2025 Savings and Investments Union push explicitly frames this home bias and market fragmentation as why EU savings flow abroad — often into US equities — instead of financing domestic scale-ups and the green transition.
Frequently asked
- What is home bias?
- Home bias is the tendency of investors to hold a far larger share of domestic assets than global market weights would justify. A US investor holding 80% domestic stocks when the US is roughly 60% of world market cap exhibits home bias, leaving the portfolio under-diversified against local economic and currency shocks.
- Why does home bias matter for Europe?
- Home bias matters for Europe because fragmented, domestically-anchored savings prevent capital from flowing to the most productive pan-European firms and transitions. The EU's 2025 Savings and Investments Union
Glossary · capital markets union
Capital Markets Union (CMU) is the EU's long-running project to integrate fragmented national capital markets into a single deep pool of equity and debt funding, reducing bank dependence, easing cross-border investment, and channelling household savings into productive risk capital across the bloc.
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- What causes home bias?
- Home bias is driven by information asymmetry, currency and hedging costs, transaction frictions, regulatory steering of pension and insurance assets, and behavioural familiarity with domestic names. Investors perceive home assets as less risky because they know them better, even when global diversification would lower portfolio volatility for the same expected return.
- How does home bias differ from consumption smoothing?
- Home bias describes over-concentration in domestic assets, while consumption smoothing
Glossary · consumption-smoothing
Consumption-smoothing is the household behaviour of holding consumption steady across time by borrowing and saving against expected lifetime income, rather than letting spending track current income. It is the central prediction of the permanent-income and life-cycle models, where transitory income shocks are buffered, not consumed.
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- Is home bias declining over time?
- Home bias has fallen gradually as cross-border investing cheapened, but it remains large and persistent across nearly every country. Even in deeply integrated markets, investors still hold domestic assets well above global benchmark weights, which is why the puzzle of why diversification stays incomplete remains an active research and policy question.