The present invention relates to a mounting rail system (100) comprising a mounting rail (1) with an elongate profiled mounting rail (2) which has a longitudinal extent (L), delimits an interior (I) and has an elongate coupling opening (20), and an elongate busbar (4), which extends longitudinally (L) in the interior (I) of the profiled mounting rail (2), wherein the busbar (4) has at least one electrical conductor (40) for electrically connecting electrical or electronic components (30) via the coupling opening (20). The mounting rail system (100) further has a tapping element (10), which is detachably inserted into the interior (I) via the coupling opening (20) and byway of a contact portion (5) is electrically coupled to the busbar (4). The tapping element (10) further has a supply element (6), which is provided on the outside in relation to the mounting rail (1) and is electrically connected by way of electrical connecting element (7) to the contact portion (5) via an opening (24), independent of the coupling opening (20), in the profiled mounting rail (2) in order to supply the electrical tapping by the contact portion (5) from the busbar (4) via the supply element (6) on the outside.