ISTB vs SPY
iShares Core 1-5 Year USD Bond ETF vs State Street SPDR S&P 500 ETF Trust
Which is better, ISTB or SPY?
Short Term Bond against Large Cap Blend.
ISTB has a lower expense ratio. SPY led over 1Y, 3Y, 5Y and the full window.
MarketXLS is not an investment adviser. This comparison is generated automatically from market data and is for information only. A Best mark means the better reading on that one measure, not a recommendation to buy.
Side-by-Side Comparison
| Metric | ISTB | SPY |
|---|---|---|
| Expense Ratio | 0.06%Best | 0.09% |
| AUM | $5.1B | $804.7B |
| Dividend Yield | 4.28% | 0.98% |
| Holdings | 7,038 | 505 |
| YTD Return | +0.74% | +12.19%Best |
| 1Y Return | +1.97% | +18.53%Best |
| 3Y Return (annualized) | +5.12% | +20.88%Best |
| 5Y Return (annualized) | +1.95% | +12.69%Best |
| Volatility (annualized) | 2.2%Best | 14.2% |
| Max Drawdown | -50.1% | -34.1%Best |
| $10,000 over 5 years | $11,014 | $18,173Best |
| Fund Family | iShares by BlackRock (US) | State Street Investment Management |
| Category | Fixed Income | Equity |
| Style | Short Term Bond | Large Cap Blend |
| Inception | Oct 18, 2012 | Jan 22, 1993 |
Not shown on this pair: Top 10 Weight.
Volatility and max drawdown are measured over the window both funds cover: Oct 22, 2012 to Sep 9, 2026 (13.9 years).
ISTB vs SPY growth
Month-end closes. Both lines start at 0% in the first month shown, so the gap between them is the difference in growth across that window. The full view is available from the range buttons; it is not the opening view here because over the whole period one of these two funds moves so much further than the other that its line would sit flat on the axis.
ISTB vs SPY Performance
iShares Core 1-5 Year USD Bond ETF (ISTB) is an ETF from iShares by BlackRock (US) and State Street SPDR S&P 500 ETF Trust (SPY) is an ETF from State Street Investment Management. Over the past year ISTB returned +1.97% while SPY returned +18.53%. Year to date, ISTB is up 0.74% versus a gain of 12.19% for SPY.
Over three years, ISTB compounded at +5.12% per year against +20.88% for SPY; over five years the annualized figures are +1.95% and +12.69% respectively. Across the full 14-year window we track, SPY has the edge at +13.39% annualized vs +0.94%.
Past performance does not guarantee future results.
Risk: Volatility and Drawdowns
SPY has been the more volatile fund, with annualized monthly volatility of 14.2% compared with 2.2% for ISTB. Lower volatility generally means a smoother ride, though it often comes with lower long-run returns.
The deepest peak-to-trough decline in our data was -50.1% for ISTB and -34.1% for SPY. Drawdown depth is what each fund did in the worst stretch of the window measured above.
The two funds' monthly returns correlate at 0.42. They move together some of the time, and apart the rest.
Fees and Cost Over Time
ISTB charges 0.06% per year while SPY charges 0.09%. On a $10,000 position that is $6 vs $9 annually, a gap of $3 per year that compounds over a long holding period. On income, ISTB currently yields 4.28% against 0.98% for SPY.
Holdings Overlap
At least 0.2% of SPY's money is in holdings ISTB also owns.
Stated as a floor: for ISTB, our book for it covers 52.2% of that fund, so a holding it does not list is one we cannot count as shared. The real figure is this or higher.
We cannot see either book well enough to say how much of this pair is duplicated.
3 positions in common, counted across the 2,218 positions we hold weights for in ISTB and 504 in SPY, against full books of 7,038 and 505.
You are not choosing between two funds in isolation.
Whichever of ISTB and SPY you pick has to sit alongside everything else you own. Add the rest and see what the combination actually holds.
Free for up to 10 holdings. No account needed.
Frequently Asked Questions
Which is cheaper, ISTB or SPY?
ISTB has an expense ratio of 0.06% while SPY charges 0.09%. ISTB is the cheaper option, by $3 a year on a $10,000 investment.
Which performed better, ISTB or SPY?
Over the past year ISTB returned +1.97% vs +18.53% for SPY, so SPY leads on 1-year performance. Over the longest common window we track (14 years), ISTB annualized +0.94% vs +13.39% for SPY. Past performance does not guarantee future results. This is information, not a recommendation.
Which is riskier, ISTB or SPY?
SPY has been the more volatile fund at 14.2% annualized versus 2.2% for ISTB. Worst drawdown: ISTB -50.1% vs SPY -34.1%.
Should I hold both ISTB and SPY?
ISTB and SPY have a monthly-return correlation of 0.42, so their returns are far enough apart for the mix to behave differently from either one alone. This is information, not a recommendation.
Which pays a higher dividend, ISTB or SPY?
ISTB yields 4.28% while SPY yields 0.98%, so ISTB currently pays the higher dividend yield.
Is SPY better than ISTB?
ISTB has a lower expense ratio. SPY led over 1Y, 3Y, 5Y and the full window. Which one suits a particular account depends on what it is for. This is information, not a recommendation.