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ETF fund flows August 2026: VOO takes $27.5bn as Vanguard closes on iShares

Written by Ultumus | Sep 23, 2026, 3:49:11 PM

Key takeaways

  • Vanguard’s VOO took $27.54bn of net new money in August 2026 and closed the month at $1.05trn — 16.5% of the US top-20 ETF market on its own.

  • iShares’ IVV lost $11.18bn and State Street’s SPY $4.61bn. Two S&P 500 trackers gave back $15.8bn in the same month a third took $27.5bn.

  • Vanguard is now $1.4bn behind iShares in US ETF assets — $4.693trn against $4.695trn — and out-gathering it by almost three to one.

  • iShares holds 40.9% of European top-20 issuer assets, four times Xtrackers in second place.

  • Crypto is the most concentrated segment in the market. iShares accounts for 50.7% of top-20 crypto ETF assets and 76% of the segment’s net August inflows.

August 2026 ETF fund flows at a glance

The world’s 20 largest ETF issuers held $18.93trn at the end of August 2026, and Vanguard led net flows with $67.22bn, ahead of iShares on $37.26bn and Invesco on $28.66bn. Beneath those three numbers, August tells four distinct stories: a three-way split in S&P 500 trackers, a US asset race that is now within rounding distance, a European market that keeps consolidating, and a crypto segment held by a single issuer.

Concentration is the backdrop to all of it. iShares, Vanguard and SPDR together hold 72.2% of global top-20 issuer assets, and the twenty largest ETF products in the world hold $6.46trn between them. In a market this top-heavy, a single product’s flow number moves the league table.


The S&P 500 split: one tracker takes, two give back

VOO, IVV and SPY track the same index. In August they went in opposite directions. VOO took $27.54bn. IVV lost $11.18bn. SPY lost $4.61bn.

Cost is the usual explanation — VOO charges 3 basis points against SPY’s 9 — but it does not account for IVV, which competes with VOO on price. What is left is distribution and habit. VOO has become the default ticker for US large-cap beta, and default tickers compound.

The rest of the US top 20 was broadly positive. QQQ added $16.94bn, VTI $7.61bn, GLD $5.42bn and SPYM $5.30bn. Only six of the twenty lost money, and outside IVV and SPY the largest outflow was XLK at $1.31bn.

The gap matters beyond the three tickers. VOO now holds $1.05trn against IVV’s $886.7bn and SPY’s $814.6bn — 16.5%, 13.9% and 12.8% of the US top-20 universe. A year of flows at August’s rate would put real daylight between first and second place in a segment the market has treated as interchangeable for a decade.
 
Figure 1: Net new money by ticker, US top 20 ETFs, August 2026. Source: Ultumus ETF analytics.


Vanguard is $1.4bn from the US lead

In the US top-20 issuer universe, iShares holds $4,694.5bn and Vanguard $4,693.1bn — a gap of $1.43bn, or 30.53% of the market against 30.52%. August flows were not close: Vanguard $58.95bn, iShares $21.13bn. On that pace the ranking changes within weeks.


Globally iShares remains comfortably ahead, $6.28trn to $5.06trn. The difference is Europe, where iShares holds $1.51trn against Vanguard’s $302.7bn.

Issuer Global AUM Share August net flow
iShares $6.28trn 33.2% +$37.26bn
Vanguard $5.06trn 26.7% +$67.22bn
SPDR $2.32trn 12.3% +$4.93bn
Invesco $1.21trn 6.4% +$28.66bn
Schwab $619.8bn 3.3% +$9.78bn
Xtrackers $410.9bn 2.2% +$6.20bn
JPMorgan $409.5bn 2.2%     +$7.89bn
Dimensional $319.8bn 1.7% +$3.68bn
Amundi $309.2bn 1.6% +$4.13bn

Table 1: Largest ETF issuers by assets, global top-20 universe, 31 August 2026. Share is of the $18.93trn top-20 total.


Europe consolidates, Asia divides

Europe’s top 20 issuers held $3.68trn, and iShares took $15.57bn of August’s flows — more than Vanguard ($7.00bn) and Xtrackers ($5.42bn) combined. Invesco added $4.74bn and Amundi $4.13bn. Concentration runs to the product level too: CSP1 and IWDA between them hold 35.6% of European top-20 ETF assets. The largest single European inflow was VWRA at $3.34bn, with gold tracker SGLD adding $1.54bn.

Asia, at $673bn across its top 20 issuers, split cleanly. Korea and Taiwan gathered: Mirae Asset $1.76bn, Cathay $1.20bn, Samsung KODEX $1.10bn. Greater China paid out: CSOP lost $981m, ChinaAMC $788m and the Tracker Fund of Hong Kong $505m.


Where the money went, by asset class

Asset class Top-20 AUM Largest inflow Most concentrated
Equity $15.34trn  Vanguard +$50.13bn iShares 30.9%
Fixed income $3.03trn iShares +$18.30bn iShares 43.5%
Commodities  $457.3bn SPDR +$5.46bn SPDR 33.8%
Crypto $138.5bn iShares +$4.37bn iShares 50.7%

Table 2: Global top-20 universes by asset class, 31 August 2026.

Two points stand out. SPDR was the largest gainer in commodities on gold demand while shedding $3.67bn from its equity book — the same firm, opposite directions. And iShares now holds more than half of top-20 crypto ETF assets, a share no issuer holds in any other asset class.


Fixed income and gold did the quiet work

Equity took the headlines, but August’s second story was bonds. The global fixed income top 20 held $3.03trn, and iShares and Vanguard took $34.97bn of the month’s flow between them — $18.30bn and $16.67bn. Behind them the field was tight: JPMorgan $3.55bn, Schwab $3.22bn, SPDR $3.16bn, PGIM $1.77bn and PIMCO $1.74bn. iShares holds 43.5% of the segment, its strongest position in any asset class outside crypto.

Gold ran through the month on both sides of the Atlantic. GLD added $5.42bn in the US and SGLD $1.54bn in Europe, and SPDR took $5.46bn of the $457.3bn global commodities segment. Invesco followed with $2.27bn, iShares $1.65bn and Amundi $1.38bn. The largest commodity outflow was Legal & General at $963m.


Active ETFs: $1.73trn and a two-horse race

The 20 largest active ETF issuers held $1.73trn. Dimensional ($307.0bn) and JPMorgan ($305.3bn) hold 35.5% of it between them. August flows were led by American Century at $7.06bn, then JPMorgan $6.34bn, iShares $5.38bn and Capital Group $5.14bn.

At product level the largest active inflow was AVLV at $3.44bn — an American Century fund, which is where most of that issuer’s $7.06bn came from. The largest active ETF by assets remains DFAC at $49.4bn.