ETF researchers are attributing outflows of $11 billion from the 10 largest European equity exchange-traded funds to fears that Great Britain will vote to exit the European Union tomorrow.

For months the sentiment has shifted for and against the "Remain" or "Leave" camps, with London's bookies today favoring a stay vote. However, the Financial Times poll of polls gives a slim edge to Leave, 45-44.

“With possible Brexit on the horizon, investors have exited these ETFs in droves in 2016,” said Todd Rosenbluth, director of ETF & Mutual Fund Research at S&P Global Market Intelligence, following the release of the company's report highlighting fund outflows year to date through June 15.

U.S.-based investors have pulled out of the U.K. faster than Brits themselves because of Brexit fears, according to Morningstar's research, which reported that global U.S. mutual funds have reduced U.K. stock holdings in the first quarter to the lowest point in four years.

The hardest hit ETF funds belong to WisdomTree, BlackRock and Vanguard, with Leave fears sucking $4.36 billion from WT's Europe Hedged Equity Fund (HEDJ), $3.55 billion from iShares MSCI Eurozone (EZU) and $1.6 billion from Vanguard's FTSE Europe (VGK), the largest of the European focused ETFs with $12.68 billion in assets, according to the Rosenbluth report.

Behind the polls and Ladbrokes (betting) politics are real potential consequences to critical trade alliances. "If British citizens decided to leave the EU, a period of great uncertainty would begin," said Jean-Michel Six, S&P Global Ratings chief economist for EMEA (Europe, Middle East and Africa). "The United Kingdom would need to renegotiate a trade agreement with the rest of the European Union as well as bilateral deals with all other non-EU countries.” The outcome “could trigger a decline in investments in the U.K."

A spokesman for Vanguard, in an e-mail, said the company doesn't “really comment on cash flow, particularly short-term cash flows. Frankly, it's not something we pay too much attention to,” he added. “We are focused on helping our clients reach their financial goals by being the world's highest value provider of investment products and services.”

Via email an iShares spokeswoman, who declined to comment on Brexit, referred to BlackRock's May 2016 publication, the Global ETP Landscape. In it, she noted, Europe equity fared the worst, with outflows in May of $5.1 billion, which includes all globally listed ETFs that track European equities: single-country funds that track Germany and Italy, plus ETFs that track European equity indexes -- EZU is an example. Of that total, broad funds, ETFs that track only European equity indexes, amounted to $3.9 billion.

“Year-to-date redemptions now exceed $20 billion, an abrupt reversal from 2015 inflows of $80 billion,” she wrote. “ECB stimulus has not yet alleviated concerns over economic growth and low inflation.”

WisdomTree did not respond to several attempts to obtain comment.
 
“I don't think the outflows are solely to Brexit fears, but they are not helping,” said Rosenbluth. “Europe has been a poor-performing equity market in 2016 and investors have pulled assets and repositioned some of their ETF flows to U.S. fixed income products.”