Q3 GDP Grows 3.4% as September Inflation Climbs to 3.6%

A strong quarter that hides a weaker September

The U.S. economy grew faster than expected over the summer. On October 29 the Bureau of Economic Analysis put real GDP growth at a 3.4% annual rate for July through September, up from 2.2% in the second quarter.1116 That beat forecasts of 3.1% to 3.2% and came in just above the Atlanta Fed's final GDPNow estimate of 3.3%.1215 It was also the fastest growth since the third quarter of 2025, when the economy expanded at 3.9%.1520

The timing makes the number harder to read than usual. The release came the day after the Federal Reserve held rates steady with two officials voting for a hike, five days before the November 3 midterm elections, and at the same moment as a separate report showing inflation picking up again in September.15 Taken together, the two reports show strong output over the quarter, while September looks worse: prices rose faster, households earned less after inflation, and the extra spending came from savings. That second picture is the one that should shape how the 3.4% figure is read.

What drove the growth

BEA said the quarter's gain came from higher investment, consumer spending and government spending, partly offset by lower exports.1214 Imports also rose. They are subtracted when GDP is calculated, and in the agency's breakdown capital goods other than autos were the largest contributor to them.14 Measured as a plain quarter-over-quarter change rather than an annual rate, the economy grew about 0.8%.1718

The contribution figures show that much of the speed-up came from sources that tend to swing from quarter to quarter. Consumer spending added about 2.52 percentage points and inventory building added 1.61, while trade subtracted 3.32 points, mostly because of the jump in imports.12 Government added 0.90 points, about twice what the Atlanta Fed model had expected. Federal spending more than accounted for the government increase, led by nondefense consumption.1218 One analysis noted that household spending added roughly the same amount as in the spring. That means the move from 2.2% to 3.4% came mainly from inventories and government, not from stronger consumer demand.15

The longer-running demand trend is still solid. Real final sales to private domestic purchasers, which strip out inventories, trade and government, grew at a 4.9% rate, up from 4.6% in the second quarter.12 Most coverage treats that figure as the better guide to demand, and it is the one to watch when BEA revises the quarter.

The technology factor

For a tech audience, the most notable part of the report is where the investment went. Equipment spending was concentrated in information processing gear, mainly computers and peripherals.18 One calculation from BEA's detailed tables found that computers and software together added 1.09 percentage points, about 32% of the quarter's growth.17 Two cautions apply. Much of that equipment is imported, which offsets part of the gain in the GDP math, and BEA does not measure AI spending as its own category.1719 Analysts call it AI investment, but the government's data cannot yet confirm how much of it is AI-related, as opposed to a general recovery in equipment and inventories.19

AI investment does seem to be keeping private demand strong.15 One strategist also listed the AI boom among inflation pressures that have not fully shown up yet.1

Two different inflation readings

Outlets described inflation in the same release in opposite ways. Some said price growth slowed in the third quarter, because the PCE price index rose at a 2.1% annual rate, down sharply from 5.0% in the second quarter.121819 Others, reporting on the monthly data released the same morning, said inflation sped up in September.2127

Both descriptions use accurate numbers. The quarterly figure looks calm because consumer prices fell in June and barely rose in July after an energy-driven spring surge, and those months pull down the third-quarter average.2 In my reading, the 2.1% figure reflects that averaging more than any real cooling. The more recent monthly data point the other way. Headline PCE inflation rose to 3.6% year over year in September, up from 3.4%, and the 0.5% monthly gain was the largest since March.2122 Core PCE, which excludes food and energy, rose 0.3% for the month and 3.1% for the year, up from 3.0%. Both readings were the highest since May.22 Inflation is moving away from the Fed's target, not closing in on it.

The consumer price index released two weeks earlier showed the same pattern. CPI rose 0.6% in September and 3.7% from a year earlier, up from 3.4% in August.2 Gasoline jumped 9.1% in the month and accounted for more than half of the overall increase. Energy prices were up 20.4% over the year.2 Reporting ties the energy surge to the war with Iran, which began in late February and has restricted global oil supply. Gasoline neared $4.50 a gallon in late September.8

Calling this an energy-only problem understates it. Core CPI rose 0.3% for a second straight month and came in above forecasts, and its annual rate climbed to 2.6% from 2.4%.39 TD Economics described the price pressure as fairly broad, with firmer readings in shelter, core goods and several services outside housing, and said those services have been running above 3% for months.3 Producer prices rose 6.3% from a year earlier, a sign of more cost pressure ahead.4

The two inflation gauges are also out of their usual order. Core PCE has run above core CPI every month since November 2025, and the gap in August was the widest since 2010.23 This matters for policy because the Fed sets its 2% target using PCE. On the Fed's preferred measure, underlying inflation is above 3%, not the 2.6% shown by CPI.2330

Consumers spent more by saving less

In current dollars, consumer spending rose 0.5% in September, slightly below the 0.6% forecast. Personal income rose only 0.2%.21 After adjusting for inflation, the figures look weaker: real disposable income fell 0.3%, and real spending was essentially flat, up just $2.6 billion.26 Households kept spending by saving less. The saving rate fell to 3.8% from 4.0%, its lowest level since October 2022.2324

This is the clearest mismatch with the GDP headline. Consumer spending is still the largest part of growth, but going into the fourth quarter it is being supported by a shrinking savings cushion, not rising real income. One analysis noted that both headline and core PCE inflation now exceed recent hourly wage growth of about 3.0%.29 That leaves households with real wage losses that cannot go on indefinitely.

What it means for the Fed

The Fed raised its target range to 3.75%–4.00% on September 16, its first increase in three years, and held it there on October 28 in a 10–2 vote.2630 Its statement described economic activity as expanding at a strong pace and said more information would help officials set policy.12 Officials' September projections put core PCE inflation at 3.4% for 2026. September's core increase was close to the monthly pace needed to reach that level, so the Fed's own forecast assumes inflation keeps rising through December.23

Some market commentators questioned why the Fed did not raise rates again, given growth this strong and PCE inflation at 3.6%.22 One estimate put the odds of a December hike at about 84.5% shortly after the data came out.25 Strong output, inflation above 3% and falling real incomes add up to a strong case for raising rates again. I expect December to be a live meeting with tightening as the more likely outcome, unless the October and November data change course.

Revisions could change the picture

The 3.4% figure is preliminary. BEA built the advance estimate before much of September's data arrived and will revise it on November 25 and December 23. Since 2002, the advance figure has moved by about half a percentage point on average by the third estimate.1215 Recent quarters show how much that can matter: the fourth quarter of 2025 was cut from 1.4% to 0.5%, and the second quarter of 2026 was raised from 1.5% to 2.2%.12

Revisions are unlikely to change the main conclusion. The economy grew strongly in the third quarter, helped by tech equipment spending, inventory building and federal spending. It ended the quarter with inflation rising, real incomes falling and consumers saving less, while energy costs from the Iran war push prices higher. Even after revisions, the coverage points to slower growth and stickier inflation ahead.