Who Owns the Market Now? The Rise of ETFs in US and UK Equities
Twenty years ago, ETF tickers were still a niche detail at the bottom of a trading screen. By 2026, exchange‑traded funds are one of the main ways global investors hold US and UK equities, and their footprint is reshaping how those markets trade.
Recent industry reports put some hard numbers on that shift. A global ETF study finds that ETFs now represent about 11.2% of equity assets in the US and 6.1% in Europe, with lower but fast‑growing shares in Canada and Asia‑Pacific. A Franklin Templeton review of 2025 calls it “a milestone year” and notes that ETFs account for 37% of total fund assets globally, up from 26% four years earlier — a sign that, in many portfolios, mutual funds have become “secondary expressions rather than the primary vehicle of choice".
The UK’s own asset-management data tell a similar story from a London vantage point. The Investment Association’s 2024‑25 report shows UK‑managed investment fund assets rising to £4.9 trillion, with equities making up 49% of total assets and fixed income 28%. Index‑tracking strategies, including ETFs, now account for 35% of UK‑managed assets, up from 33% in 2023, and North American firms manage roughly three‑quarters of those tracker assets. The same report notes that North American groups now oversee 54% of UK‑managed assets under management, up from around 47% for much of the previous decade.
In practice, that means a growing share of US and UK equity market ownership is held through rules‑based vehicles that trade intraday and rebalance mechanically. In the US, sector and style ETFs tied to the S&P 500, Nasdaq and Russell indices now concentrate flows around index events: quarterly rebalances, additions and deletions, and options‑expiry dates can all trigger bursts of ETF‑linked volume that drive short‑term volatility in underlying stocks. In the UK, FTSE‑linked ETFs and index funds are a major conduit for overseas capital into London‑listed names, particularly for investors who see UK large caps as a discounted value or income play versus US growth.
This ownership shift has two important consequences for 2026:
Market moves are increasingly index‑driven. When money flows into a broad S&P 500 or FTSE 100 ETF, it supports all constituents in proportion to their weight, often regardless of near-term fundamentals. Conversely, outflows can pressure solid companies simply because they sit inside a selling index.
Control over equity capital is more global. The rise of US-domiciled ETF giants and their growing share of UK-managed tracker assets means that decisions taken in New York or Boston about product design and index inclusion now influence how pension and retail money is allocated in London.
For investors and policymakers, the picture is clear: ETFs are no longer a side note in the US and UK stock markets — they are central to how those markets behave. Any serious reading of flows, volatility and ownership patterns in 2026 has to take them into account.