24X Exchange Aligns Round Lot Rules with National Standards
Published Date: 3/9/2026
Notice
Summary
24X National Exchange is updating its rule about what counts as a 'round lot'—basically, the standard number of shares in a trade—to match a new national definition that started in November 2025. This change affects traders and brokers using 24X, making sure everyone’s on the same page with the latest rules. The update is effective immediately, so no waiting around, and it helps keep trading smooth and fair.
Analyzed Economic Effects
3 provisions identified: 3 benefits, 0 costs, 0 mixed.
24X adopts national round‑lot rule
If you trade on 24X, the Exchange changed its Rule 11.6(q)(1) so that a "Round Lot" now follows the size assigned by the primary listing market under Rule 600 of Regulation NMS instead of defaulting to 100 shares. The Exchange also updated Rule 11.20(d)(1) so the "normal unit of trading" refers to that Round Lot definition.
New round‑lot sizes and schedule
Under Rule 600 of Regulation NMS (implemented November 3, 2025), a Round Lot for NMS stocks is set by average closing price: $250.00 or less = 100 shares; $250.01–$1,000.00 = 40 shares; $1,000.01–$10,000.00 = 10 shares; $10,000.01 or more = 1 share. Adjustments occur on a semiannual basis using a one‑month Evaluation Period (March for May assignments; September for November assignments), and a stock that becomes an NMS stock during an operative period has a Round Lot of 100 shares.
Rule change effective immediately
The Exchange filed the change on February 24, 2026 and requested a waiver of the usual 30‑day operative delay; the Commission waived the delay and designated the proposal operative upon filing, so the conforming rule changes are implemented immediately. The filing states there are no additional operational changes to the affected rules.
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