What Is Sell in May and Go Away?

“Sell in May and go away” is a market saying based on the historical observation that returns have sometimes been stronger from roughly November through April than from May through October.

It is a description of a long-term seasonal tendency, not a rule that every investor should sell in May.

Where does the phrase come from?

The saying is associated with historical return differences between the two halves of the year. Several explanations are often suggested: lower summer trading activity, holidays, institutional schedules, and recurring capital flows.

Those explanations may be plausible, but they do not make the pattern permanent or universal. Markets can rise strongly during the summer, and individual stocks can behave very differently from a broad index.

Does Sell in May always work?

No. A historical average includes years when the tendency did not appear. Leaving the market purely because of a calendar date can mean missing a rally, while staying invested can be difficult during a weak period.

Before relying on the phrase, check:

• which market and dates were tested;
• the number of historical years;
• individual summer outcomes, not only the average;
• how recent history compares with the full sample;
• current economic and market conditions.

How should you use the idea?

Treat it as a question to research, not an investment instruction. You can compare the May-to-October window across a broad index or a stock you already follow, then examine the distribution of past returns and weak years.

For a broader explanation, read Seasonal Patterns in Stocks. To understand why a historical tendency is not a forecast, see Historical Market Patterns vs. Trading Signals.

Explore a specific company in Ticker Analysis, or see public historical pages for Microsoft, NVIDIA, and Amazon.

Historical outcomes do not predict future returns and are not investment advice.