Level II Market Data
Level II is commonly used to describe a deeper view of displayed bids and offers beyond the single best bid and ask.
What you see
A Level II display typically shows multiple price levels, displayed size and market participants or venues associated with those quotes. It can help illustrate where visible liquidity is currently concentrated.
What it can help explain
Order-book depth can show whether a market looks thick or thin near the current price, how much visible size sits at nearby levels, and whether the inside quote is supported by additional liquidity behind it.
What it does not show
Displayed orders are not commitments to remain in place. They can be changed or cancelled quickly. Not all trading interest is necessarily displayed in the same way. Large visible orders can also be interpreted incorrectly if viewed without actual trade flow.
Level II versus Time & Sales
Level II shows resting displayed interest. Time & Sales shows completed transactions. One is a view of the current book; the other is a record of what actually traded. Traders often compare both, but neither provides certainty about what comes next.
Avoid “mind reading”
The most dangerous use of Level II is treating every visible order as proof of a participant’s intent. Use it as microstructure context—spread, depth, changes in liquidity—not as a magical prediction tool.
Common questions
Does Level II show every order?
No. It reflects displayed data available through the relevant feeds and venues; not all trading interest appears as visible resting size.
Can Level II predict the next move?
No. It can provide execution and liquidity context, but visible orders can change rapidly and do not reveal future intent with certainty.
Example: depth can disappear
A Level II screen may show a large bid a few cents below market. If that order is cancelled as price approaches, the apparent support can vanish without ever trading. This is why displayed size should be treated as conditional information rather than a guaranteed barrier.
Source discipline
Market structure details can vary by security, venue, broker and order-routing arrangement. For formal rules and current exchange procedures, use primary sources such as the SEC, FINRA and the relevant listing/trading venue. See our Sources & Methodology.