Reliable data providers to download historical data five-minute data for S&P 500 stocks

[ZBZB]

Another source https://www.dxfeed.com/historical-tick-data/ they have some demo data from the flash crash on the link for free. From $59.

 

[calvinp239]

Have you checked out Algoseek? They can create custom minute bars and you can get detailed pricing on their website as well https://www.algoseek.com/equity-indexes/