A three-fund ETF portfolio in 2026 can be built for a blended cost of about 0.04% a year using a total U.S. stock ETF, a total international stock ETF and a total U.S. bond ETF. Using the iShares Core S&P Total U.S. Stock Market ETF (ITOT) at 0.03%, the iShares Core MSCI Total International Stock ETF (IXUS) at 0.07% and the iShares Core U.S. Aggregate Bond ETF (AGG) at 0.03%, a 60/30/10 mix costs 0.042% and carried a blended 30 day SEC yield of 1.65% as of June 30, 2026, while a 40/20/40 mix costs 0.038% and yields 2.61% [1][2][3]. The three funds held 2,499, 4,337 and 13,224 securities respectively, so the whole portfolio owns more than 20,000 positions [1][2][3].
What goes into a three-fund ETF portfolio
The three-fund approach uses one fund per major asset class and leaves security selection to the index. The U.S. stock sleeve, ITOT, tracks the S&P Total Market Index and held 2,499 stocks with $94.1 billion in net assets as of June 30, 2026; its ten largest holdings, led by Nvidia (NVDA) at 6.63%, Apple (AAPL) at 5.81% and Microsoft (MSFT) at 3.79%, made up 32.11% of the fund, and information technology was 35.66% of assets [1]. The international sleeve, IXUS, tracks the MSCI ACWI ex USA IMI Index with 4,337 holdings across developed and emerging markets; its top ten positions were only 14.95% of assets, led by Taiwan Semiconductor Manufacturing (TSM) at 4.36%, and Japan was the largest country at about 15% [2]. The bond sleeve, AGG, tracks the Bloomberg US Aggregate Bond Index with 13,224 holdings, 46.26% in Treasuries and 23.43% in mortgage pass through securities, and an effective duration of 5.80 years [3].
Some investors substitute an S&P 500 fund such as the iShares Core S&P 500 ETF (IVV) for the total market fund. IVV also costs 0.03%, but it is more concentrated: its top ten holdings were 36.37% of assets on June 30, 2026, against 32.11% for ITOT, and it excludes small and mid caps [1][4]. Small caps have mattered in 2026: the iShares Russell 2000 ETF (IWM) rose 20.5% in price from its December 31, 2025 close of $246.16 to $296.54 on July 21, 2026 [5].
Allocations, costs and expected yields in 2026
The table applies each fund's June 30, 2026 expense ratio and 30 day SEC yield (ITOT 0.98%, IXUS 2.05%, AGG 4.51%) to four common allocations. Yields are a starting point, not a promise; the SEC yield of a bond fund moves with interest rates and the equity yields move with prices and payouts [1][2][3].
| Allocation (ITOT / IXUS / AGG) | Blended expense ratio | Blended 30 day SEC yield | Cost per $100,000 per year |
|---|---|---|---|
| 60% / 30% / 10% | 0.042% | 1.65% | $42 |
| 50% / 20% / 30% | 0.038% | 2.25% | $38 |
| 40% / 20% / 40% | 0.038% | 2.61% | $38 |
| 30% / 10% / 60% | 0.034% | 3.21% | $34 |
Calculations by DataPorium from the fund fact sheets [1][2][3]. Investors can track the three funds daily on DataPorium's ETF page.
What the last ten years would have looked like
Each sleeve has a distinct return profile. Over the ten years to June 30, 2026, ITOT returned 15.01% annualized, IXUS 10.07% and AGG 1.52% [1][2][3]. Over one year the order flipped at the top: IXUS returned 27.35%, ITOT 23.05% and AGG 3.80% [1][2][3]. A 60/30/10 portfolio therefore earned roughly 22.4% over the year to June 30, 2026 before rebalancing effects, with international stocks doing more than their share. The bond sleeve is there for the bad years, although 2022 showed its limits: ITOT lost 19.51%, IXUS 16.35% and AGG 13.06% that year, so even a 40/20/40 mix fell about 16% [1][2][3].
Why costs and breadth matter more than picking the top fund
The case for the three-fund structure rests on arithmetic. A 0.04% cost is $4 a year per $10,000; a fund charging 1% takes $100 from the same balance every year, and the gap compounds to a meaningful share of returns over decades. Breadth removes the single stock and single sector bets that dominated 2026 returns elsewhere: technology was 35.66% of ITOT, but it was diluted by the international and bond sleeves [1]. The price to earnings ratio of the U.S. sleeve was 29.20 times on June 30, 2026, against 19.20 times for IXUS, and a fixed allocation forces an investor to trim the expensive sleeve and add to the cheaper one at each rebalance [1][2].
- Rebalance on a schedule, for example once a year or when a sleeve drifts 5 percentage points from target, rather than on headlines.
- Hold bonds in tax deferred accounts where possible, because AGG's 4.51% yield is mostly ordinary income, while equity index ETFs rarely distribute capital gains [3].
- Set the bond share from the spending horizon: AGG's 5.80 year duration means a 1 percentage point rise in rates would cut its price by roughly 5.8% [3].
- Accept that the U.S. sleeve is top heavy: ten stocks were 32.11% of ITOT, a feature of market cap weighting in 2026 [1].
The counterpoint is fair: a three-fund portfolio will never beat the market, and in a year like 2026, when semiconductor funds gained far more than broad indexes, it will look slow. It is designed to capture market returns at near zero cost, not to outrun them.
Three index ETFs, more than 20,000 securities and a total cost near 0.04% a year is a portfolio most investors can hold through any cycle without adjustment.
Key takeaways
- ITOT (0.03%), IXUS (0.07%) and AGG (0.03%) combine into a portfolio costing 0.034% to 0.042% a year depending on the mix [1][2][3].
- Blended 30 day SEC yields as of June 30, 2026 ranged from 1.65% (60/30/10) to 3.21% (30/10/60) [1][2][3].
- Ten year annualized returns to June 30, 2026: ITOT 15.01%, IXUS 10.07%, AGG 1.52% [1][2][3].
- The U.S. sleeve is concentrated (top ten 32.11%, technology 35.66%); the international and bond sleeves dilute that [1][2][3].
- In 2022 all three funds fell, so the bond sleeve reduces but does not remove drawdowns [1][2][3].
Frequently asked questions
What is a three-fund portfolio?
It is a portfolio made of one total U.S. stock index fund, one total international stock index fund and one total bond index fund, held in fixed proportions and rebalanced periodically. With ETFs such as ITOT, IXUS and AGG the total cost is about 0.04% a year [1][2][3].
What is a good allocation for a three-fund portfolio in 2026?
Common splits run from 60/30/10 for long horizons to 30/10/60 for investors near spending. Investors may consider setting the bond share by how soon they need the money, since AGG's 5.80 year duration makes it sensitive to rate moves [3].
How much income does a three-fund ETF portfolio pay?
Using June 30, 2026 SEC yields of 0.98% for ITOT, 2.05% for IXUS and 4.51% for AGG, a 60/30/10 mix yields about 1.65% and a 40/20/40 mix about 2.61% [1][2][3].
Should the U.S. fund be an S&P 500 ETF or a total market ETF?
Both cost 0.03%. IVV holds 504 large caps with a 36.37% top ten weight, while ITOT holds 2,499 stocks with a 32.11% top ten weight, so the total market fund adds small and mid caps and slightly less concentration [1][4].
Sources & References
- [1] iShares Core S&P Total U.S. Stock Market ETF (ITOT) fact sheet as of June 30, 2026
- [2] iShares Core MSCI Total International Stock ETF (IXUS) fact sheet as of June 30, 2026
- [3] iShares Core U.S. Aggregate Bond ETF (AGG) fact sheet as of June 30, 2026
- [4] iShares Core S&P 500 ETF (IVV) fact sheet as of June 30, 2026
- [5] DataPorium ETF prices
