If the provider is not contacted, you can go to the provider’s help section and find out which customer support email address to forward to scam email.
The FTC can and should also be contacted about email and Internet scams you find, especially if they are scams meant to obtain personal financial information from you.
The BBB’s primary use is to protect consumers against bad businesses. By reporting a business scam to the BBB, you prompt them to investigate the business. If that business’s practices prove fraudulent, the BBB will report them as such, warning other consumers not to get involved.