September 2025 was another month with healthy inflows for the U.S. ETF industry.
These inflows occurred in a volatile but overall positive market environment in which investors around the globe acted nervous over any political and economic news. In more detail, global markets entered September with a wary eye on inflation, monetary policy, and geopolitics. By month’s end, equities had mostly advanced, bonds saw a sharp repricing of yields, and investors were left weighing whether the world economy was entering a new phase of resilience or fragility.
For most investors the speech of Federal Reserve Chair Jerome Powell at the annual Jackson Hole conference on September 22 was one of the most important events of the month. A lot of investors were surprised when Powell struck a more dovish tone than many had anticipated, acknowledging that monetary policy may now be restrictive and hinting at possible adjustments. That single intervention helped drive down shorter-dated Treasury yields and revived expectations for a September rate cut.
The strong results presented during the earnings season drove the trends in the equities markets. Around three-quarters of S&P 500 companies beat second-quarter earnings forecasts, demonstrating that profit growth remains intact even as the macro environment cools. That said, technology remained volatile since investors had to manage a delicate balance between optimism and caution.
European equities and bonds were buffeted by mixed macroeconomic data. The eurozone composite PMI remained just above the critical 50 level, indicating modest growth. That resilience, alongside easing inflation, gave the European Central Bank some room to maneuver. Yet investors were wary—fiscal strains in several member states and concerns over the long-term debt trajectory kept upward pressure on long-dated yields. In addition to this, the unclear political situation in France has added some volatility to the European bond markets.
The performance of European equities was steadier than many expected, particularly in financials and industrials. That said, the performance of the industry sector industrials was clearly driven by the performance of producers of weapons and other military equipment. A softer U.S. dollar also offered relief for euro-denominated assets. But the region remains sensitive to global trade shifts, especially as Washington pursued reciprocal tariffs with trading partners, adding a layer of uncertainty for export-heavy economies such as Germany.
Asia delivered both surprises and headwinds. Japan’s second-quarter GDP beat forecasts, and core machinery orders rose, hinting at underlying strength. Equity markets in Tokyo gained as a result, aided by a weaker yen.
China, however, remained a source of volatility. Ongoing trade negotiations with the United States saw a temporary truce, supporting risk sentiment. Yet concerns about domestic demand and property-sector fragility lingered. Broader emerging Asia benefited from a weaker dollar, which lifted both equities and local currency bonds. Investors also noted that capital inflows into Asian debt markets increased as the Fed’s dovish tilt reduced pressure on local currencies. That said, it looks like the decline of the U.S. dollar was the pivotal driver for the good performance of securities markets in the emerging markets. Local-currency bonds rallied, and credit spreads tightened as investors sought higher yields in a supportive currency environment. Still, risks remained. New U.S. tariffs on India over Russian oil imports underscored how geopolitics can quickly cut across improving fundamentals.
By the close of September, markets had absorbed a potent mix of dovish central-bank rhetoric, solid earnings, and ongoing geopolitical uncertainty. Equities advanced globally, while bonds staged a rally at the short end but continued to wrestle with fiscal concerns further out the curve. Investors head into autumn with optimism about growth resilience, but also with an awareness that stretched valuations, rising debt burdens, and political flashpoints could quickly reverse sentiment.
From an U.S. ETF industry perspective, the performance of the underlying markets led, in combination with the estimated net flows, to increasing assets under management from $12,211.9 bn as of August 31, 2025, to a new all-time high of $12,719.5 bn at the end of September. At a closer look, the increase in assets under management of $507.5 bn for September was driven by the performance of the underlying markets (+$365.0 bn), while estimated net inflows contributed $142.5 bn to the growth of the assets under management.
Assets Under Management by Asset Type
As for the overall structure of the U.S. ETF industry, it was not surprising equity ETFs ($9,695.7 bn) held the majority of assets, followed by bond ETFs ($2,145.3 bn), alternatives ETFs ($570.7 bn), commodities ETFs ($277.0 bn), mixed-assets ETFs ($27.0 bn), and money market ETFs ($3.7 bn).
Within the current market environment, it is not surprising that the assets under management for all asset types, with the exception of mixed assets, marked an all-time high at the end of the month. These numbers show that the main headwinds on the markets have turned into tailwinds which were pushing the assets under management up over the course of the month.
Graph 1: Market Share, Assets Under Management in the U.S. ETF Industry by Asset Type, September 30, 2025
Source: LSEG Lipper
ETF Flows by Asset Type
The U.S. ETF industry enjoyed healthy estimated net inflows (+$142.5 bn) over the course of September despite some market insecurities in the equity and bond markets. These inflows drove the overall inflows in ETFs up to $928.6 bn for the year 2025 so far.
Given the strong recovery of equity markets in the second quarter of 2025 and the relatively good results presented by most of the leading companies, it is not surprising that the inflows in the U.S. ETF industry for September were driven by equity ETFs (+$86.4 bn), followed by bond ETFs (+$39.0 bn), commodities ETFs (+$11.9 bn), alternatives ETFs (+$4.4 bn), mixed-assets ETFs (+$0.5 bn), and money market ETFs (+$0.4 bn).
The relatively high inflows into bond ETFs, despite the insecurities about the future level of debt in the U.S., might be a sign that U.S. investors are still looking for safe haven investments given the unclear outlook for future earnings from some companies caused by the unclear consequences for corporate earnings from the announced new tariff regime in the U.S.
Graph 2: Estimated Net Sales by Asset Type, September 2025 (USD Billions)
Source: LSEG Lipper
More generally speaking, it can be said that the flow numbers in the U.S. ETF industry indicate that U.S. investors are in risk-on mode.
Assets Under Management by Lipper Global Classifications
To examine the U.S. ETF markets in further detail, a review of the Lipper global classifications will lead to more insights on the structure and concentration of assets within the U.S. ETF industry. At the end of September 2025, the U.S. ETF market was split into 142 different peer groups (Lipper Global Classifications). The highest assets under management at the end of September were held by funds classified as Equity U.S. ($5,408.1 bn), followed by Equity Global ex U.S. ($969.1 bn), Equity U.S. Small & Mid Cap ($947.4 bn), Bond USD Medium Term ($545.3 bn), and Equity U.S. Income ($447.5 bn). These five peer groups accounted for $8,317.4 bn, or 65.39%, of the overall assets under management in the U.S. ETF segment, while the 10-top classifications by assets under management accounted for $9,806.9 bn, or 77.10%.
Overall, 16 of the 142 peer groups each accounted for more than 1% of assets under management. In total, these 16 peer groups accounted for $10,853.9 bn, or 85.33%, of the overall assets under management.
Graph 3: Ten Largest Lipper Global Classifications by Assets Under Management, September 30, 2025 (USD Billions)
Source: LSEG Lipper
The peer groups on the other side of the table showed some funds in the U.S. ETF market are quite low in assets and their constituents may face the risk of being closed in the near future. They are obviously lacking investor interest and might, therefore, not be profitable for their respective fund promoters.
Graph 4: Ten Smallest Lipper Global Classifications by Assets Under Management, September 30, 2025 (USD Billions)
Source: LSEG Lipper
ETF Flows by Lipper Global Classifications
The net inflows of the 10 best-selling Lipper classifications accounted for $107.3 bn. In line with the overall sales trend for September, equity classifications (+$75.6 bn) gathered the majority of flows by asset type on the table of the 10 best-selling classifications by estimated net inflows for September 2025. Given the overall fund flow trend in the U.S. ETF industry, it was not surprising that Equity U.S. (+$43.7 bn) was the best-selling Lipper global classification for September. It was followed by Commodity Precious Metals (+$11.8 bn) and Bond USD Medium Term (+$10.0 bn).
The flows at the classification level show that U.S. investors seem to have further bought into U.S. large caps after the market turmoil in April to participate in the market recovery. In addition, they also want to participate from the strong performance of precious metals, as some of these metals hit one all-time high after the other.
Despite the fact that there are classifications from various asset types on the table of the 10 best-selling classifications, these numbers show that the U.S. ETF segment is highly concentrated when it comes to the estimated net flows by classification. Generally speaking, one would expect the flows into ETFs to be concentrated since investors often use ETFs to implement their market views and short-term asset allocation decisions. These products are made and, therefore, are easy to use for these purposes.
Graph 5: Ten Best- and Worst-Lipper Global Classifications by Estimated Net Sales, September 2025 (USD Billions)
Source: LSEG Lipper
On the other side of the table, the 10 classifications with the highest estimated net outflows for September faced slightly higher lower overall outflows for the month (-$9.2 bn) than those for August (-$9.1 bn).
Alternative Equity Leveraged (-$6.1 bn) was once again the classification with the highest outflows for the month. It was bettered by Equity Europe (-$0.8 bn), Bond Other (-$0.6 bn), Equity Germany (-$0.5 bn), and Equity Sector Healthcare (-$0.5 bn).
Assets Under Management by Promoters
A closer look at assets under management by promoters in the U.S. ETF industry also showed high concentration, with only 114 of the 449 ETF promoters covered in this report holding assets at or above $1.0 bn—accounting for $12,658.7 bn in assets under management. The largest ETF promoter in the U.S.—iShares ($3,814.8 bn)—accounted for 29.99% of the overall assets under management, ahead of the number-two promoter—Vanguard ($3,651.5 bn)—and the number-three promoter—SPDR ($1,732.8 bn).
Graph 6: The 10 Largest ETF Promoters by Assets Under Management, September 30, 2025 (USD Billions)
Source: LSEG Lipper
The 10-top promoters accounted for 89.61% of the overall assets under management in the U.S. ETF industry. This meant, in turn, the other 439 fund promoters registering at least one ETF for sale in the U.S. accounted for only 10.39% of the overall assets under management. With regard to the concentration of the U.S. ETF industry by promoter, it is noteworthy that there were nine ETF promoters accounting for more than 1% of the overall assets under management each.
Please read our report: “U.S. ETF Industry – Review of the Concentration of Assets Under Management at the Promoter Level” for more information on the distribution of the assets under management at the promoter level.
ETF Flows by Promoters
Since the U.S. ETF market is highly concentrated when it comes to the assets under management by promoter, it was not surprising that eight of the 10 largest promoters by assets under management were among the 10-top selling ETF promoters for September. iShares was the best-selling ETF promoter in the U.S. for September (+$50.7 bn), ahead of Vanguard (+$31.4 bn) and Invesco (+$6.6 bn).
Graph 7: Ten Best-Selling ETF Promoters, September 2025 (USD Billions)
Source: LSEG Lipper
The flows of the 10-top promoters accounted for estimated net inflows of $118.5 bn. As for the overall flow trend in September, it was clear that some of the 449 promoters (94) faced estimated net outflows (-$9.1 bn in total) over the course of the month.
Assets Under Management by ETFs
There were 4,561 instruments (primary share classes/portfolios [4,492] and [convenience] share classes [69]) listed as ETFs in the Lipper database at the end of September. Regarding the overall market pattern, it was not surprising assets under management at the ETF level were also highly concentrated. Only 872 of the 4,492 ETFs (primary share classes = portfolios) held assets above $1.0 bn each. These ETFs accounted for $12,132.9 bn, or 95.39%, of the overall assets in the U.S. ETF industry. The 10 largest ETFs in the U.S. accounted for $3,887.2 bn, or 30.56%, of the overall assets under management.
Graph 8: The 10 Largest ETFs by Assets Under Management, September 30, 2025 (USD Billions)
Source: LSEG Lipper
Estimated Net Flows at the ETF Level
A total of 2,359 of the 4,492 ETFs (primary share classes = portfolios) analyzed in this report showed net inflows of more than $10,000 each for September, accounting for inflows of $202.6 bn. This meant the other 2,133 ETFs faced no flows, or net outflows, for the month. Upon closer inspection, 328 of the 2,359 ETFs posting net inflows enjoyed inflows of more than $100 m during September—for a total of $171.3 bn. The best-selling ETF for September was iShares Core S&P 500 ETF, which enjoyed estimated net inflows of $18.7 bn. It was followed by SPDR Gold Shares (+$4.4 bn) and iShares S&P 100 ETF (+$4.4 bn).
Graph 9: The 10 Best-Selling ETFs, September 2025 (USD Billions)
Source: LSEG Lipper
The flow pattern at the fund level indicated there was a lot of turnover and rotation during September, but it also showed the concentration of the U.S. ETF industry even better than the statistics at the promoter or classification levels since the 10 best-selling ETFs account for inflows of $48.9 bn.
Given its size and the overall trend for net sales at the promoter level, it was not surprising that four of the 10 best-selling ETFs for September were promoted by iShares. These iShares ETFs accounted for estimated net inflows of $18.1 bn. That said, the numbers for iShares show the concentration in fund flows even better than other measures, since the vast majority of the inflows into ETFs classified as Alternative Currency Strategies was invested in just one ETF issued by iShares.
The views expressed are the views of the author, not necessarily those of LSEG.
This article is for information purposes only and does not constitute any investment advice.
