National Best Bid and Offer

National Best Bid and Offer - National Best Bid and Offer is the Security and Exchange Commission rule that requires the brokers to guarantee that the customers receive the best prevailing ask price when they purchase the securities and the best prevailing bid price when they sell securities. This incorporates prices from all competing market centers, exchanges, and refers to the price at the time of entry into the market. The National Best Bid and Offer (NBBO) is the bid and ask the average person will see. Day traders using Level two market maker screens see all the bids and offers for any given particular stock.