Education

Why a Market Order Can Become More Expensive Near the Open

By Walid Mograbi · 2026-05-22 · 2 min read

Opening conditions often make execution less calm, so order choice matters more than many beginners expect.

Why this lesson matters

Opening conditions often make execution less calm, so order choice matters more than many beginners expect.

The core idea

• The open can carry wider uncertainty and thinner calm liquidity.
• Market orders are most exposed when price discovery is still settling.
• Execution control matters more during volatile windows.

Practical example

A trader pressing a market order right after the open may receive a noticeably different fill than expected because the book is still adjusting.

Common mistakes to avoid

• Assuming the open behaves like the middle of the session.
• Using market orders reflexively.
• Ignoring the price-discovery process.

Quick checklist

• Opening conditions
• Liquidity
• Spread
• Need for speed
• Order type

Key takeaway

A good lesson improves judgment, risk control, and execution discipline before it changes action.

Important caution

Fast execution is not the same as efficient execution.

Further reading

• https://www.nyse.com/network/article/trading-etfs-market-orders-explained
• https://www.investor.gov/introduction-investing/investing-basics/how-stock-markets-work/types-orders