The takeaway
Twilio Inc shows a moderate seasonal pattern over 10 years of data — strongest in July (+5.9%) and softest in September (−2.1%).
Right now
In July, the stock has risen 80% of years, averaging +5.9%, about +3.7 pts better than the S&P 500.
The full picture
Twilio Inc's most dependable month has been July, higher in 8 of 10 years; September has been its least reliable, up just 40% of the time.
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Month by month
The stock's clearest edge over the S&P 500 lands in May (+11.9 pts); it has trailed the market most in March (−6.7 pts).
“vs S&P” is Twilio Inc’s average for a month minus the S&P 500’s average for that same month — isolating Twilio Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, July has closed higher 60% of the time versus 80% across the last 10 years — the pattern is weakening.
Figures are the typical (median) July 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
The seasonal story is really one month's story — July. It has closed higher in 8 of 10 Julys, a concentration the rest of the calendar can't touch.
Read it with one caveat: the average (+5.9%) runs well ahead of the median (+2.5%), so a handful of outsized years — not steady strength — do much of the lifting. Few months are steadier: July's returns vary by just 8.1% year to year, and even its worst July in 10 years lost only 3.5% — the gentlest downside anywhere on its calendar. Better still, that strength is the stock's own and not just a buoyant market — July has outpaced the S&P 500 by +3.7 points on average. Few peers keep such company in July — the typical stock clears it just 61% of the time.
It doesn't stand entirely alone — January, June, and December have leaned firm as well, if less emphatically. The weaker half of the year is plainer: September has been the soft spot — the weakest of 4 months that average a loss (−2.1%), and the edge isn't year-round — the stock has trailed the S&P 500 in March, October, and September. Its roughest month on record was a −47.5% October in 2016 — a reminder of how hard even a seasonal name can fall.
The pattern has softened of late, July's last five years slipping below its longer-run record.
For a stock this dependable in July, the sharper question is the rest of the year — outside its strong stretch, the calendar gives far less to lean on. With returns that swing hard year to year, the signal is best held loosely.
Short answers on the stock's best month (July), its worst (September), and whether it really trades seasonally.
Yes, to a moderate degree. Since 2016 its best month (July, +5.9%) has run well ahead of its worst (September, −2.1%) — the heatmap above shows how steady that gap has been year to year.
July has been the strongest, averaging +5.9% and closing higher in 8 of 10 years since 2016.
It's the weakest, averaging −2.1% — 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