iShares 20+ Year Treasury Bond ETF (TLT) Seasonality
Recurring seasonal patterns for TLT — the calendar windows where iShares 20+ Year Treasury Bond ETF has historically tended to rise or fall, with the win rate (how often it repeated) and average return for each, based on the last 10 years of price history.
TLT seasonality at a glance
Over the last 10 years, TLT's strongest seasonal window has been Mar 15 – Apr 4: it ended higher in 10 of 10 years (100% win rate) with an average return of +2.23% across a 20-day hold. On the weak side, TLT has historically declined between Sep 8 – Oct 8, falling in 10 of 10 years (average -3.89%).
In total, our analysis finds 396 recurring seasonal windows for iShares 20+ Year Treasury Bond ETF — 217 bullish and 179 bearish. The next high-win-rate window, Aug 20 – Sep 19, opens in 24 days. These figures describe historical behaviour only — not a forecast.
TLT's upcoming & recent seasonal patterns
Holding period:10-day20-day30-dayOrdered by season — windows opening soon first, plus a couple of recently completed high-performers. Holding-period colors help you compare durations at a glance.
| Status | Seasonal window | Hold | Avg return | Win rate | This year |
|---|---|---|---|---|---|
| Completedended 23d ago | Jun 14 – Jul 4 | 20d | +1.59% | 80% | +0.07% |
| Completedended 23d ago | Jun 4 – Jul 4 | 30d | +1.88% | 80% | +0.38% |
| Upcomingin 24d | Aug 20 – Sep 19 | 30d | -1.45% | 80% | — |
| Upcomingin 27d | Aug 23 – Sep 12 | 20d | -1.11% | 80% | — |
| Upcomingin 28d | Aug 24 – Sep 23 | 30d | -1.46% | 80% | — |
| Upcomingin 36d | Sep 1 – Oct 1 | 30d | -1.80% | 80% | — |
| Upcomingin 37d | Sep 2 – Oct 2 | 30d | -2.02% | 80% | — |
Win rate = how often the pattern repeated in the same direction. Average return = the mean move across all analysed years. Past performance does not guarantee future results.
Explore TLT seasonality in full
See the seasonal curve chart, filter by win rate and return, and track upcoming windows — free during beta.
TLT seasonality FAQ
What has historically been the best month to buy TLT stock?
Based on the last 10 years of price data, TLT's strongest seasonal window starts in March: Mar 15 to Apr 4, which ended higher in 10 of 10 years (100% win rate) with an average return of +2.23%. Past seasonal patterns do not guarantee future performance.
What is TLT's strongest seasonal pattern?
TLT's highest-win-rate pattern in our data is the Mar 15 – Apr 4 window (20-day hold): up in 10 of the last 10 years with an average move of +2.23%.
When has TLT historically performed worst?
TLT's weakest recurring window has been Sep 8 to Oct 8, declining in 10 of 10 years with an average return of -3.89%.
How reliable are TLT's seasonal patterns?
Each TLT pattern is scored by its historical win rate — the share of the last 10 years it repeated in the same direction. TLT currently shows 396 recurring windows (217 bullish, 179 bearish). Seasonality describes historical tendencies only; it is not a prediction, and past performance does not guarantee future results.
What is TLT stock seasonality?
Stock seasonality is the tendency of a stock to perform in a similar way during the same period each year. By analysing iShares 20+ Year Treasury Bond ETF's price history across many years, SeasonalityX identifies recurring calendar windows — exact start and end dates — where TLT has repeatedly risen (bullish) or fallen (bearish). Each pattern is scored by its win rate and average return so you can judge how reliable and how strong it has been.
Seasonality is one input among many — it works best alongside your own research and risk management. Learn more in our guide to seasonal analysis and the tutorials.