When Is The Best Day of the Week To Buy Stocks? Here's What Data Shows

Market timing remains a persistent question for investors at all levels. If you’d invested $10,000 in the S&P 500 index at the beginning of 2005 and held it through 2024, your investment would have grown to $71,750—representing an annual return of 10.4%. However, attempt to actively trade in and out of positions, and the math shifts dramatically. According to research compiled by CNBC, missing just the best 60 days in the market during that two-decade span would have reduced your returns to just $4,712, a -3.7% loss. This striking contrast highlights why understanding trading patterns can be valuable, especially when considering the best days to buy stocks versus times to avoid taking action.

Understanding Weekly Market Patterns: Why Some Days Underperform

For decades, market observers have noted the “Monday Effect”—a pattern where stocks tend to open lower at the beginning of the week. George Kailas, CEO and co-founder of Prospero.ai, explains that this phenomenon results from a combination of factors accumulating over the weekend. “News is building up while markets are closed, and traders are adjusting their positions based on that weekend information,” Kailas notes. This often creates downward pressure when markets reopen.

Julia Khandoshko, CEO of the European broker Mind Money, provides additional context: “News accumulates while markets are closed during weekends, and this results in prices being dragged lower at the open on Mondays. After processing news all weekend long, investors may decide to sell on Monday, which could bring the stock price down.” For short-term traders specifically, Monday has historically represented a less favorable day to initiate sell orders, making it potentially advantageous for those looking to accumulate shares at lower opening prices.

However, it’s important to recognize that the Monday Effect has diminished in strength over recent years as markets have become more efficient and global participation has increased.

Tuesday Through Friday: When Investors Have Better Opportunities To Buy

Research consistently shows that mid-week trading presents a more favorable environment for purchasing stocks. Tuesdays through Thursdays have historically demonstrated stronger performance patterns. “Investors have had time to digest weekend news, and overall sentiment resets,” explains Khandoshko. “This makes Tuesday particularly attractive for buying because the emotional reactions from Monday have settled, making it a less stressful time to invest.”

Kailas emphasizes that Thursdays also warrant attention for active investors. He publishes his weekly newsletter on Thursdays specifically because he observes that investor engagement and market activity peak during this period. Fridays round out the stronger trading days, with Benzinga’s research suggesting that end-of-week trading can be optimal for selling, as stocks have typically moved throughout the day and likely reached higher price levels. The relevant company news has usually been digested and reflected in the market by close of business Friday.

The combination of these mid-week and end-of-week patterns suggests that strategic investors can potentially identify better entry points by focusing their purchase activity on Tuesday through Thursday, then potentially exiting positions on Friday.

Beyond Day-of-Week Trading: What Actually Matters For Portfolio Success

While understanding trading patterns can provide tactical advantages, it’s crucial to maintain perspective on what truly drives portfolio growth. Kailas stresses that these daily patterns are significantly less important for investors with a multi-year or multi-decade time horizon: “The bigger drivers of portfolio growth remain earnings, interest rates and diversification strategies. Trying to perfectly time trades by weekday can lead to overtrading, which hurts more than it helps.”

Multiple financial institutions confirm this view. J.P. Morgan Wealth Management notes that numerous factors beyond the day of the week can affect market volatility, including overall economic conditions, global events, holidays, and unexpected developments. Chase Bank researchers have identified several elements that matter far more than your choice of trading day:

Company fundamentals: Review the company’s revenue trajectory, debt levels, and management quality before deciding to buy or sell.

Overall market trends: Monitor inflation data, employment reports, and interest rate announcements, as these create short-term market fluctuations.

Your personal risk tolerance and investment timeline: Ensure your portfolio aligns with your specific financial goals and time horizon to avoid making emotional decisions during market volatility.

The reality is that identifying the best days to buy stocks provides marginal advantages at best. Even when Monday underperformance is evident, the gains from buying low on Monday pale in comparison to the gains from staying invested through years of market cycles. A dollar invested in 2005 that stayed invested through 2024 generated far superior returns compared to one that was traded frequently—even if every trade was timed to the optimal day of the week.

For investors considering when to buy or sell, consulting with a qualified financial advisor remains the most prudent step. A professional can help ensure your investment decisions and timing strategy align with your unique situation, risk tolerance, and long-term financial objectives.