SPY vs TLT: Correlation
Measured on weekly returns over the past three years, SPDR S&P 500 ETF Trust (SPY) and iShares 20+ Year Treasury Bond ETF (TLT) carry a correlation of 0.12, a weak link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are SPY and TLT?
Across a 3-year window, the weekly returns of SPY and TLT correlate at 0.12, weak. The relationship has been stable: the 1-year correlation (0.18) sits close to the 3-year figure. Stretching to 5 years gives 0.12, with an annualized covariance of 22.5 %².
By 3-year correlation, TLT places #3967 of the 4755 assets tracked against SPY. The last year tells two different stories: SPY led by 20.3 percentage points, +20.6% for SPY against +0.3% for TLT. Do not treat this figure as fixed: across three years the rolling one-year correlation ranged all the way from -0.31 to 0.56.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
SPY vs TLT: side by side
| SPY (SPDR S&P 500 ETF Trust) | TLT (iShares 20+ Year Treasury Bond ETF) | |
|---|---|---|
| 1-year return | +20.6% | +0.3% |
| 5-year return | +82.4% | -34.0% |
| Volatility (ann.) | 14.5% | 13.5% |
| Beta vs S&P 500 | 1.00 | 0.11 |
| Max drawdown (3Y) | -18.8% | -14.8% |
| Dividend yield | 1.01% | 4.75% |
| Expense ratio | 0.09% | 0.15% |
| Assets under management | $795.3B | $41.5B |
| Sector / category | ETF · US Large Cap | ETF · Bonds |
SPY, State Street Investment Management's Large Blend fund, carries $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield. On the fund side, TLT sits in the Long Government category at iShares, with $41.5B under management, a 0.15% expense ratio, a 4.75% trailing dividend yield.
Year-by-year returns
| Year | SPY | TLT |
|---|---|---|
| 2022 | -18.2% | -31.2% |
| 2023 | +26.2% | +2.8% |
| 2024 | +24.9% | -8.1% |
| 2025 | +17.7% | +4.2% |
| 2026 | +13.7% | -2.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are SPY and TLT good diversifiers for each other?
Yes. With a correlation of 0.12, SPY and TLT have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
FAQ
What is the correlation between SPY and TLT?
As of 2026-08-27, the correlation of weekly returns between SPY and TLT is 0.12 over 3 years, 0.18 over 1 year and 0.12 over 5 years.
Is TLT a good diversifier for SPY?
Yes. With a correlation of 0.12, SPY and TLT have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
What does a correlation of 0.12 mean?
On the −1 to +1 scale, 0.12 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/spy-vs-tlt.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/spy-vs-tlt/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: SPY correlations · TLT correlations
