HKEX Reduces Minimum Price Fluctuation by 50%: Trading Costs Decrease, New Changes in Hong Kong Stock Trading Rules

On August 3, 2026, the Hong Kong Stock Exchange officially implemented the second phase of reducing the minimum price fluctuation for stocks. For ordinary investors, the term "minimum price fluctuation" may be unfamiliar, but it directly determines the minimum change interval for each order price, and also directly affects the bid-ask spread and trading costs. This adjustment is a microcosm of HKEX's series of market microstructure reforms in recent years - from quotation mechanisms to trading lots, from derivative price limits to spot settlement cycles, Hong Kong is being reshaped into a more efficient, cheaper, and transparent market.

What is the Minimum Price Fluctuation? What Changed This Time

The minimum price fluctuation is a term in the Hong Kong securities market, referring to the minimum unit for each price change of each security, that is, the minimum price interval that investors can choose when inputting buy/sell orders. According to HKEX arrangements, the core content of the second phase adjustment is: for securities in the HK$0.5 to HK$10 range (applicable to all currency units including Hong Kong dollars), the minimum price fluctuation is reduced by 50% from HK$0.01 to HK$0.005.

The scope of applicable securities is the same as the first phase implemented in August 2025, covering stocks, real estate investment trusts (REITs), equity warrants, etc., but not including exchange-traded products (ETPs), debt securities, exchange-traded options and structured products (including bull/bear certificates and derivative warrants). For mainland investors, the securities applicable to the reduced minimum price fluctuation are mainly Hong Kong Connect eligible stocks, which means Southbound funds can also directly enjoy this institutional dividend.

First Phase Effectiveness Significant: Spread Narrowed by 35%, Trading Speed Increased by 30%

This adjustment is not an isolated decision, but is based on the effectiveness of the first phase of reform. On August 4, 2025, HKEX implemented the first phase of reform, reducing the minimum price fluctuation for securities in the HK$10 to HK$20 range from HK$0.02 to HK$0.01, and for the HK$20 to HK$50 range from HK$0.05 to HK$0.02. According to data disclosed by HKEX, as of July 4, 2026, compared with before the implementation, the bid-ask spread of applicable securities narrowed by an average of 35%, and order matching time was shortened by an average of 30%.

HKEX Chief Operating Officer Liu Biyin said that since the first phase of narrowing the bid-ask spread reform, the bid-ask spread in the Hong Kong securities market has narrowed significantly, trading costs have decreased, and overall liquidity has improved; the second phase arrangement will further enhance market efficiency and liquidity. HKEX Group Deputy CEO Yao Jiaren also pointed out that HKEX is committed to increasing the vitality and liquidity of the Hong Kong stock market by launching different market microstructure enhancement measures.

What Does Reducing Price Fluctuation Bring? Four Benefits

HKEX said that reducing the minimum price fluctuation can bring four benefits to the market:

• Reduce Trading Costs: Smaller price fluctuations help narrow the bid-ask spread, allowing investors to trade closer to real market prices, and round-trip trading costs随之下降.
• Improve Trading Efficiency: Orders are more likely to be executed at expected prices, reducing slippage and waiting time caused by large price intervals.
• Optimize Price Discovery: Prices can more accurately reflect the actual value of the security, reducing pricing deviations and market noise.
• Enhance International Competitiveness: The market microstructure is further aligned with mainstream international markets, consolidating Hong Kong's position as an international financial center.

More Than Price Fluctuation: HKEX Reform "Combination Punch"

Standardization of Trading Lots, Lowering Entry Thresholds

In fact, the reduction of price fluctuation is only one of HKEX's multiple reforms in 2026. On June 30, HKEX implemented the optimization reform of trading lots: the lower limit of the trading lot value guidance was reduced from HK$2,000 to HK$1,000, and the number of shares per lot in the whole market was uniformly standardized to eight standard specifications: 1 share, 50 shares, 100 shares, 500 shares, 1,000 shares, 2,000 shares, 5,000 shares, and 10,000 shares. The new rules lower the entry threshold for small funds and also simplify the cognitive cost of trading units. Chen Yuxuan, an analyst at non-bank securities at Huatai Securities, pointed out that this measure reshapes the micro-trading mechanism of Hong Kong stocks, significantly improves market operation efficiency, effectively reduces investment thresholds, and lays the foundation for subsequent market unification reforms.

Derivative Elasticity Amplified, Settlement Cycle Brewing Shortening

In terms of derivatives, on June 9, HKEX expanded the T+1 session price limit for six major index futures contracts such as Hang Seng Index futures and Hang Seng Tech Index futures from ±5% to ±6%, further enhancing market price discovery capabilities. At the basic settlement level, HKEX issued a consultation document in April this year, planning to shorten the Hong Kong stock spot settlement cycle from T+2 to T+1, expected to be implemented in the fourth quarter of 2027, to align with global mainstream market rules, improve capital efficiency and reduce settlement risks.

Horizontally, most A-share stocks have a minimum price change unit of 0.01 yuan, while Hong Kong stocks have reduced the securities in the HK$0.5 to HK$10 range to HK$0.005, which is more refined than A-shares in the low-price and mid-price segments, and the space for narrowing spreads and optimizing trading costs is larger - this is the intuitive embodiment of the flexibility of Hong Kong stock trading rules, and also the reason why many investors are turning their attention to Hong Kong stocks.

Institutional Dividends Plus Capital Water: What is the Attraction of Hong Kong Stocks

While continuously optimizing at the institutional level, the capital side of Hong Kong stocks is also warming up. Securities Times quoted Wind data as saying that on August 4, Southbound funds had a net inflow of HK$2.57 billion; since this year, except for a net outflow in May, Southbound funds have maintained a strong allocation intensity, with net purchases in June and July reaching HK$27.11 billion and HK$62.87 billion respectively, showing a clear trend of capital return. Since June 26, as of August 4, the Hang Seng Index and Hang Seng Tech Index have risen by 12.03% and 10.89% respectively, market risk appetite has gradually recovered, and tech growth and core assets are still important directions for capital allocation.

The research team of Bank of Communications International believes that Hong Kong stocks have a foundation for further upward movement, and recommends a "dumbbell" structure allocation: one end is high-elastic tech growth assets, including internet platforms, AI applications, cloud computing and consumer electronics industry chain; the other end is reflation beneficiaries and cash flow-stable energy, materials and financial sectors. The research team of Guoyuan International Securities reminds that in the short term, Hong Kong stocks may still show a "index fluctuation, sector rotation" pattern, and the conditions for trend upward movement are not yet fully mature.

It needs to be reminded that Hong Kong stocks have no price limit, high volatility, and are affected by multiple variables such as overseas liquidity changes, geopolitical factors and AI industry verification processes. Institutional dividends reduce trading costs and participation thresholds, but cannot eliminate the volatility risk of the market itself. For cross-border investors, understanding changes in rules, making good use of tools, and at the same time doing a good job in position and risk management, can only go far and steadily in the highly internationalized Hong Kong market.