How long does a recession last?

Why 1945 is the dividing line

Across the whole record, back to 1857, the average is 17.0 months across 34 recessions. That number is much higher, and it is the wrong one to quote for anything happening now.

Nineteenth-century downturns were structurally different: no central bank until 1913, no deposit insurance, no automatic stabilisers, and a monetary regime that turned banking panics into multi-year contractions. The longest in the record ran 65 months, from Nov 1873 to Mar 1879. Nothing since the war has come close. Quote the postwar figure unless you specifically mean the pre-war economy.

What "how long" actually measures

The NBER dates recessions from peak to trough. The peak is the last month of the expansion and the trough is the last month of the contraction, so the recession itself is the months in between. That is what the lengths on this page count.

Two things follow, and both matter if you are quoting this. The trough is not recovery: it is the month things stopped getting worse, and output can take much longer to return to the prior peak. And these dates are assigned in hindsight, often a year or more after the fact, by a committee reviewing revised data. Nobody knows a recession's length while it is running.

The honest limits

• 13 postwar recessions is a small sample. An average of 10.2 months hides a real range of 2 to 18. Treat it as a rough centre of gravity, not an expectation for the next one.
• The record opens mid-recession. USREC begins in Dec 1854, already showing a contraction whose start the NBER never dated. Counting it as a 1-month recession would drag the averages down, so it is excluded from every figure here. All 35 runs are in the download; the statistics use 34.
• Dates get revised. The NBER can and does revisit its chronology, so a length quoted today can shift.
• Length says nothing about depth. The 2020 recession was the shortest on record at 2 months and among the most severe while it lasted.

Whether one is starting is a different question, and a harder one. The Recession Signal Index shows which indicators have actually led recessions and by how long, and the indicators dashboard shows where each one sits today. The full chronology is downloadable as CSV.