In natural gas wholesale trading markets, bid week is the last five business days immediately preceding the first of each month. Although the daily spot market for natural gas is active and trading can occur at any time, the largest volume of trading occurs on these five days. During this period of time, monthly transactions for baseload gas deliveries the following month are typically completed. The average bid week prices are then used to set monthly indices commonly used to price indexed gas contracts.
Bid week is also the time period during which financial positions serving as hedges for physical natural gas transactions must be converted into physical supplies. For example, all open positions in CME NYMEX Henry Hub futures close on the third business day before the end of the month.