5 Best iShares ETFs for a Core Portfolio | Investing

In the first half of 2026, BlackRock’s iShares exchange-traded funds, or ETFs, set a record for the strongest half-year inflows, at about $310 billion. The ETF industry as a whole pulled in a historic total of over $1 trillion in the first half of 2026, according to J.P. Morgan Asset Management.

A July report authored by Kristy Akullian, a chartered financial analyst (CFA) at iShares, said fund flows were “powered by a resurgence in U.S. equities and renewed demand for sector-specific exposures.”

Akullian also noted that fixed-income ETFs in the overall market pulled in nearly $292 billion during the first half of the year, as investors balanced renewed risk appetite with a continued interest in income-generating investments. That means fixed income captured nearly 30% of new ETF investments.

Two factors, working simultaneously, are adding momentum to BlackRock’s iShares ETFs: Investors are seeing an opportunity to put money to work in the market, and this is also a time of growing awareness of asset allocation and balanced portfolios.

iShares core ETFs track a broad base of domestic and international stock and bond indexes at a low cost. They’re designed to be the building blocks of a diversified portfolio.

“They are positioned competitively with the other low-cost ETFs, while offering [minimal] tracking error,” says Lei Deng, a CFA and certified financial planner (CFP) who’s the founder of Savor Financial in St. Louis.

“They have also been very consistent with their underlying index choices, rarely changing their benchmarks,” she adds.

Here are five of the most popular iShares index ETFs that could form the core building blocks of a balanced, diversified portfolio:

iShares Core S&P 500 ETF (IVV)

Many investors consider the S&P 500, which measures the performance of leading U.S. companies, to be “the market,” or at least a core component of a broader diversified portfolio.

IVV, with about $902 billion in assets under management, is in the same category as rival ETFs such as the Vanguard S&P 500 ETF (VOO) and the State Street SPDR S&P 500 ETF Trust (SPY).

“Because the index represents a significant portion of the U.S. equity market, its performance is often viewed as a gauge of overall stock market trends,” says Warren Covert, founder and principal advisor at FSO Wealth in Dallas.

“IVV is one of several exchange-traded funds that track the S&P 500, and [it] carries a 0.03% expense ratio, which is among the lowest in its category,” he says.

iShares Core MSCI EAFE ETF (IEFA)

This ETF tracks an index of large-, mid- and small-cap stocks from developed markets outside the U.S. and Canada.

For many years, international stocks underperformed the S&P 500, although that shifted in 2025, underscoring the importance of broad diversification.

IEFA is one of the core ETFs investors can consider for developed international equity exposure, with the Vanguard FTSE Developed Markets Index Fund ETF Shares (VEA) being a close counterpart, Deng says.

“Unlike IVV and VOO, however, IEFA and VEA do not track the same index,” she points out. “One key difference is country classification: VEA includes Canada and South Korea, and IEFA does not.”

IEFA’s expense ratio of 0.07% is low, although other developed-market ETFs can be cheaper. “As a financial planner, I would be comfortable using either IEFA or VEA for developed international exposure,” Deng says. “They serve a similar role in a portfolio, but I would not consider them completely interchangeable in the way IVV and VOO are.”

iShares Core MSCI Emerging Markets ETF (IEMG)

Emerging-market stocks are more volatile than those of developed markets, but at times deliver higher returns. An ETF like this one offers diversified low-cost exposure to that growth potential without single-country risk.

It tracks the MSCI Emerging Markets Index, which includes large-, mid- and small-cap equities. The largest country representations in IEMG are Taiwan, China, South Korea, India and Brazil.

“Although we typically think of South Korea as a developed country, MSCI classifies it as an emerging market. As a result, IEMG gives you exposure to South Korean stocks, while IEFA does not,” Deng says.

Its expense ratio of 0.09% is low, but higher than a domestic ETF like IVV. That’s because emerging-market stocks are often more complex to research, trade and manage due to factors like higher compliance costs.

iShares Russell 1000 Growth ETF (IWF)

This ETF, with about $127 billion under management, holds 366 U.S.-domiciled stocks, with the largest holdings being well-known growth names such as Nvidia Corp. (NVDA), Apple Inc. (AAPL), Alphabet Inc. Class A (GOOGL), Broadcom Inc. (AVGO) and Microsoft Corp. (MSFT).

Richard Siminou, founder of Siminou Wealth Management in New York, uses this ETF in portfolios for both younger investors and clients nearing retirement.

“A 62-year-old today may need this money to last 30 years or more,” he says. “Cutting growth exposure to near zero at retirement solves for short-term volatility and creates a longevity problem in its place.”

The Russell 1000 Growth Index is also concentrated in mega-cap technology, Siminou notes, so it overlaps considerably with what an investor may already own through an S&P 500 fund.

“That overlap is the part investors tend to miss. If you hold IVV and IWF together, you are not adding as much diversification as the two different names suggest; you are tilting toward growth,” Siminou says. “That can be the right call, but it should be an intentional decision rather than an accident.”

iShares Core U.S. Aggregate Bond ETF (AGG)

With about $138 billion in assets, this is the second-largest fixed-income ETF, behind the Vanguard Total Bond Market ETF (BND).

AGG’s 30-day SEC yield is 4.68%. It’s composed of investment-grade bonds with a weighted average maturity of over eight years, putting it in the intermediate bond category. Nearly half its holdings are in U.S. Treasurys.

This ETF is designed to generate income, which can counteract the effects of a broad portfolio decline when stocks dip. For retirees, that may mean selling fewer stocks in a down market. For younger investors, it provides portfolio ballast, which can help smooth returns.

“AGG carries an expense ratio of 0.03% and is generally intended to provide income and diversification rather than long-term capital appreciation,” Covert says.