Not quite. Bisexual means potentially being attracted to both cisgender men and cisgender women to some degree. Pansexual means potentially being attracted to anyone regardless of that person's biological/birth sex, their current physical sex, their gender identity, or their gender expression.
I say "potentially" being attracted because it's not attraction to everyone; just as with any other orientation, a pansexual person will find some individuals attractive and find others as not attractive. It's just that, in regards to being pansexual, the individual's sex and gender identity are irrelevant to whether that person is seen as attractive.