Market: US GDP growth in Q3 2026 — ≥3.0%
Market probability: 51%
ProbGap forecast: 64%
Gap: +13 percentage points
The setup
Prediction markets have started repricing the probability that U.S. real GDP growth reaches at least 3.0% annualized in Q3.
The market now puts the probability at roughly 51%.
But the latest economic data suggest the odds may still be higher.
Our current estimate:
ProbGap: 64%
That leaves a +13 percentage-point gap between our forecast and the market.
What changed?
The biggest signal comes from the Atlanta Fed's GDPNow model.
Its estimate for Q3 real GDP growth jumped from 4.4% to 5.1% annualized following the latest economic releases.
The increase wasn't driven by a single component.
GDPNow's estimate for real personal consumption expenditure growth increased from 3.6% to 4.1%, while estimated government expenditure growth rose from 1.3% to 2.3%.
Then came another strong demand signal.
August U.S. retail and food-services sales increased 1.2% month-over-month, considerably strengthening the picture of consumer activity during the quarter.
Private-sector economists have also begun revising Q3 expectations upward, with several estimates moving into roughly the 3.0–3.5% range.
Why we're above the market
A 5.1% GDPNow estimate should not be interpreted as a 5.1% GDP forecast with certainty.
Nowcasts can move substantially as new data arrive, and there is still meaningful uncertainty before the advance Q3 GDP release.
That's why our probability is nowhere near 90% or 100%.
But the question isn't whether GDPNow will be exactly right.
The threshold is only 3.0%.
With GDPNow currently more than two percentage points above that threshold, consumer spending remaining strong, and private forecasts moving higher, we think the probability distribution has shifted materially toward ≥3.0%.
Our estimate:
64% probability of Q3 real GDP growth ≥3.0%.
The prediction market currently implies approximately:
51%.
ProbGap
Market: 51%
Forecast: 64%
Gap: +13 pp
Signal: Market may be underpricing stronger-than-expected U.S. growth.
What could prove us wrong?
There is still plenty of quarter-end data to arrive.
A deterioration in consumption, weaker investment data, negative trade revisions or a significant downward move in GDPNow could quickly narrow the gap.
That makes this a forecast worth updating rather than treating as static.
The key question from here:
Does the market continue catching up with the incoming data — or does the economic data begin moving back toward the market?
We'll track both.
ProbGap tracks gaps between prediction-market probabilities and independent forecasts. Forecasts are probabilistic estimates, not certainties or financial advice.