When Howard called in a favor with Leonard, Penny set him up with Bernadette Rostenkowski, a microbiologist who worked at the Cheesecake Factory with Penny. Though Howard and Bernadette initially appeared to have little in common, they quickly bonded over their overbearing mothers and began dating.

Bernadette: Bernadette is the only woman who Howard actually has a stable relationship with even resulting later on in engagement and eventually wound up marrying her.

During this time, Howard revealed Leslie was the fifth girl he’d hooked up with… for free. Another flame was Penny’s ditzy friend from her hometown, but all in all, we can assess that Howard’s only real girlfriend was Bernadette.