Published on: 2026-07-30
TLT fell 1.65% because the long-term Treasury yields most relevant to its portfolio rose sharply, reducing the value of the bonds it owns. Its 15.13-year duration magnified the decline. The 10-year yield reached about 4.71%, but the 20- and 30-year moves explained TLT’s loss more directly.
TLT tracks Treasury bonds with more than 20 years remaining, so the 20- and 30-year yields are more relevant than the headline 10-year yield.
The 20-year yield rose 10 basis points,
and the 30-year rose 11 basis points on 29 July, while TLT’s net asset value fell 1.64%.
TLT’s 15.13-year duration implied an estimated 1.51% loss from a 10-basis-point rise in relevant yields.
Higher yields and lower bond prices are two sides of the same market repricing.
TLT can gradually earn more income after yields rise, while the price loss appears immediately.
The 10-year Treasury yield made the headlines, but TLT does not own a portfolio of 10-year notes. The iShares 20+ Year Treasury Bond ETF tracks an index of Treasury securities with more than 20 years remaining. As of 28 July, 99.87% of its market value was in that maturity range, and its weighted average maturity was 26.06 years.
EBC’s product guide similarly identifies TLT.OQ as the iShares 20+ Year Treasury Bond ETF.
The difference is visible in the yield moves below.
Treasury yield |
28 July |
29 July |
|---|---|---|
10-year |
4.61% |
4.67% |
20-year |
5.11% |
5.21% |
30-year |
5.09% |
5.20% |
The 10-year yield rose 6 basis points. One basis point equals 0.01 percentage point, so the 20-year increase of 10 basis points equalled 0.10 percentage point. The 30-year yield rose 11 basis points.
TLT closed at $82.85 on 29 July, down $1.39 or 1.65%. Its net asset value fell by a nearly identical 1.64% to $82.83.
The 10-year yield supplied the headline. The 20- and 30-year yields supplied most of the explanation.
Treasury bonds promise fixed interest and principal payments. When the market demands a higher return, those payments cannot increase, so buyers offer a lower price.
The lower purchase price raises the return available to the next buyer. Price and yield therefore move in opposite directions as the market reprices the same fixed payments.
The higher yield was not a payment TLT received. The lower bond price produced the higher yield.
The missing link between a 10-basis-point move and a 1.65% ETF decline is duration.
Duration estimates how sensitive a bond investment is to a change in yields. TLT’s effective duration was 15.13 years as of 28 July.
Estimated price change ≈ −duration × change in yield
For a 10-basis-point increase:
−15.13 × 0.10% = −1.51%
A simple $100 example produces the same result. An ETF worth $100 with a duration near 15 years would be expected to fall to approximately $98.50 after a 10-basis-point rise in the yields relevant to its holdings.
TLT’s actual net asset value fell 1.64%, close to the 1.51% estimate. The estimate is not exact because TLT holds bonds across several maturities, and their yields did not all move by the same amount.
The duration estimate shows why a 10-basis-point move in long-term yields was enough to produce a decline of roughly 1.5%.
The Federal Reserve kept the federal funds target range at 3.50% to 3.75% on 29 July. The decision passed by a 9–3 vote.
That policy rate applies to overnight borrowing. TLT owns bonds whose payments extend for more than two decades.
Long-term Treasury yields reflect expectations for inflation, economic growth, future monetary policy and demand for government debt across many years. The market can therefore demand a higher return from 20- and 30-year bonds even when the Fed leaves its overnight rate unchanged.
A rate hold freezes the current policy setting. It does not freeze the market’s view of the next ten or thirty years.
An individual Treasury bond has a maturity date. Someone holding it until maturity generally receives its stated face value, assuming the US government meets its obligations.
TLT has no single maturity date. It keeps exposure to bonds with more than 20 years remaining by replacing holdings as they move closer to maturity.
Waiting does not guarantee that TLT returns to the price someone originally paid. Its share price continues responding to long-term yields even though the US government may keep making every scheduled payment.
Rising yields create an immediate cost and a slower benefit. Existing bonds lose value as the market reprices them, while newer holdings can gradually raise the income produced by the portfolio.
TLT’s 30-day SEC yield stood at 5.04% on 28 July, while its average yield to maturity was 5.15%. Those figures describe the portfolio’s current income and return characteristics. They do not repay the 1.65% market-price decline or prevent another loss if long-term yields rise again.
Someone buying after yields have risen starts from a lower bond price and a higher portfolio yield. Someone already holding TLT absorbs the repricing before that higher income accumulates.
Higher income arrives gradually. The price loss arrives immediately.
TLT’s next move depends more directly on the 20- and 30-year Treasury yields than on the 10-year rate alone.
A softer inflation reading could lower long-term yields and support TLT. Stronger inflation could keep yields elevated and extend the pressure. Treasury auctions will provide another signal by showing how much return buyers require to absorb new government debt.
The July Consumer Price Index is scheduled for 12 August. The same week’s Treasury demand will show whether buyers are willing to accept lower yields on long-dated debt.
The 10-year headline will remain useful, but it will not tell the whole story. TLT responds most directly to the yields attached to the bonds it actually owns.
The market reduced the price of the long-term bonds inside TLT until their fixed payments offered a return competitive with higher prevailing yields. Lower prices and higher yields were part of the same repricing.
TLT does not track 10-year notes. The 20- and 30-year yields rose by 10 and 11 basis points, and TLT’s 15.13-year duration amplified those moves into an estimated price decline of about 1.5%.
No. The 4.71% figure refers to the 10-year Treasury market. TLT owns longer-dated securities and has separate measures including its 30-day SEC yield, trailing distribution yield and average yield to maturity.
Yes. Long-term yields can fall before the Fed changes its overnight rate. Lower inflation expectations, weaker growth or stronger demand for long-term Treasuries could raise TLT’s bond prices before an official rate cut occurs.
TLT has relatively low credit risk because it owns US government debt. Its interest-rate risk remains high. Using duration as a rough estimate, another 50-basis-point increase in relevant yields could imply a decline of about 7.6%, although the actual result would depend on yield changes across the portfolio.
TLT did not fall because Treasury payments suddenly became less reliable. It fell because the market demanded higher returns from long-term bonds, forcing their prices lower.
The 10-year yield attracted attention, but the 20- and 30-year yields and TLT’s 15.13-year duration explained the 1.65% loss.
