Does Price Improvement Occur More Frequently for Small or Large Limit Orders?

Price improvement tends to occur more frequently for small limit orders. Market makers who receive order flow (often via PFOF) are incentivized to provide a small amount of price improvement on smaller, less risky orders to satisfy regulatory requirements and attract retail flow.

Large orders carry higher risk for the market maker, as they are more likely to cause significant price movement, so they are less likely to receive price improvement and are often routed to the public exchange.