The takeaway
Berkshire Hathaway Inc shows a moderate seasonal pattern over 10 years of data — strongest in November (+5.9%) and softest in September (−1.6%).
Right now
In July, the stock has risen 60% of years, averaging +3.1%, about +1.0 pts better than the S&P 500.
The full picture
Berkshire Hathaway Inc's most dependable month has been November, higher in 9 of 10 years; September has been its least reliable, up just 40% of the time.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Win rate % | ||||||||||||
| Median return % | ||||||||||||
| 2025 | ||||||||||||
| 2024 | ||||||||||||
| 2023 | ||||||||||||
| 2022 | ||||||||||||
| 2021 | ||||||||||||
| 2020 | ||||||||||||
| 2019 | ||||||||||||
| 2018 | ||||||||||||
| 2017 | ||||||||||||
| 2016 |
Month by month
The stock's clearest edge over the S&P 500 lands in November (+3.5 pts); it has trailed the market most in May (−2.1 pts).
“vs S&P” is Berkshire Hathaway Inc’s average for a month minus the S&P 500’s average for that same month — isolating Berkshire Hathaway Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, November has closed higher 80% of the time versus 90% across the last 10 years — the pattern is holding.
Figures are the typical (median) November return and how often it rose — the last 5 years versus the last 10(the heatmap’s default window). This verdict stays anchored to that 10-year window even if you zoom the chart, so it never disagrees with the badges above.
In plain English
Dependability is the through-line here. November stands out, higher in 9 of 10 Novembers, but it heads a clutch of months that pull the year reliably upward.
Its average (+5.9%) and median (+6.3%) land within a hair of each other — the tell of steady, year-after-year gains rather than one outlier doing the work. Crucially, the gain is the stock's own rather than a rising tide's: November has cleared the S&P 500 by +3.5 points above the index. That consistency sets it apart from the field, where the average stock manages November only about 62% of the time.
The strength clusters rather than stands alone — November–April forms a firm stretch that carries much of the year. On the other side of the ledger, September has been the soft spot — the weakest of 3 months that average a loss (−1.6%), and the edge isn't year-round — the stock has trailed the S&P 500 in May, June, and September. Its roughest month on record was a −16.2% March in 2020 — a reminder of how hard even a seasonal name can fall.
Reassuringly, the tendency has held its shape: the recent five years still track the years behind them.
The takeaway is less about when to buy than what to expect: November aside, the stock's months offer little reliable tilt.
Short answers on the stock's best month (November), its worst (September), and whether it really trades seasonally.
Yes, to a moderate degree. Since 2016 its best month (November, +5.9%) has run well ahead of its worst (September, −1.6%) — the heatmap above shows how steady that gap has been year to year.
November has been the strongest, averaging +5.9% and closing higher in 9 of 10 years since 2016.
It's the weakest, averaging −1.6% — historically a soft spot, though it still varies from year to year.
Explore
These names have the strongest July track records on record — a starting point for comparison.
Before you trade