The minimum opening amount of soda ash futures is usually 4 lots. This means that in the soda ash futures market, investors need to buy at least four contracts every time they place an order to open a position. If the investor tries to open less than 4 lots, the system will usually prompt that "the number of positions opened is lower than the minimum opening limit", which leads to the failure to entrust the transaction successfully.

This regulation is to ensure the liquidity and stability of the market and prevent small transactions from causing unnecessary interference to the market.