Wash Sale rule applies when you sell a security at a loss and buy it again within 30 days of the sale date. When you do this you cannot deduct the loss of the original sale. Here is an example of the wash sale rule IRS: Wash Sale Rule
SPX Nd NDX trading are option trading and fall under IRS Section 1256. Section 1256 contracts are exempt from wash sale rule. The qualifying contracts are non-equity options and options on broad-based stock indexes such as SPX
