Price limits: ceiling, floor, and reference

Every trading day, each stock is given a reference price and can only move within a fixed band around it. On HOSE that band is about plus or minus 7 percent; the top is the ceiling and the bottom is the floor.

The color code

Vietnamese price boards are color-coded. The ceiling price shows in purple, the floor in cyan, and the reference in yellow. Green means up from reference, red means down.

Different bands per board

The band is wider on riskier boards: roughly 7 percent on HOSE, 10 percent on HNX, and 15 percent on UPCoM. A brand-new listing gets a much wider band on its first day.

Why it matters

A stock locked at its ceiling with buyers still queuing, or at its floor with sellers stuck, tells you about strong one-sided pressure that the band is capping for the day. Exact limits can change, so check current rules.