The takeaway
Southwest Airlines Company shows a pronounced seasonal pattern over 10 years of data — strongest in November (+9.4%) and softest in July (−3.5%).
Right now
In July, the stock has fallen 20% of years, averaging −3.5%, roughly 5.6 pts behind the S&P 500.
The full picture
Southwest Airlines Company's most dependable month has been November, higher in 9 of 10 years; July has been its least reliable, up just 20% of the time.
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Month by month
The stock's clearest edge over the S&P 500 lands in November (+7.0 pts); it has trailed the market most in July (−5.6 pts).
“vs S&P” is Southwest Airlines Company’s average for a month minus the S&P 500’s average for that same month — isolating Southwest Airlines Company’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 weakening.
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
Strip the year back and a single month does the heavy lifting: November, up in 9 of 10 Novembers while the other eleven tend to blur together.
Its average (+9.4%) and median (+10.2%) land within a hair of each other — the tell of steady, year-after-year gains rather than one outlier doing the work. That reliability comes with real swings, mind — even November ranges by 8.3% from year to year, so any single year can land far from the average. Crucially, the gain is the stock's own rather than a rising tide's: November has cleared the S&P 500 by +7.0 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–January forms a firm stretch that carries much of the year. At the other end of the calendar, July has been the soft spot — the weakest of 5 months that average a loss (−3.5%), and the edge isn't year-round — the stock has trailed the S&P 500 in July, October, and April. Its roughest month on record was a −23.9% March in 2020 — a reminder of how hard even a seasonal name can fall.
The pattern has softened of late, November's last five years slipping below its longer-run record.
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 (July), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2016 its best month (November, +9.4%) has run well ahead of its worst (July, −3.5%) — the heatmap above shows how steady that gap has been year to year.
November has been the strongest, averaging +9.4% and closing higher in 9 of 10 years since 2016.
It's the weakest, averaging −3.5% — 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