You mean the contract month of stock index futures, right? The contract month is the contract delivery month, and the quarterly month refers to the four months of March, June, September and 12. For example, you bought a stock index contract in June, and the delivery months of the contract are June, July, September and 65438+February. If you buy in July, the delivery months are July, August, September and 65438+February. The delivery months of various futures contracts are slightly different, and the delivery months of most commodity futures contracts are odd, which is related to the growth and supply of agricultural products.