This paper provides an overview of issues related to charging additional fees for health care services from people entitled to benefits financed from public funds. In particular, issue discussed was charging additional fees for medical devices used during treatment of patients, i.e. so called above‑average lens for cataract and better cochlear implants used in correction of hearing defects. The work includes a review of current opinions appearing in literature on the subject. In the content of the work authors draw attention to the ambiguity of the framework for co‑financing health care services, which is the root cause of fraud in the collection of additional fees by healthcare providers for services which are also subject of financing under a contract with the Narodowy Fundusz Zdrowia (National Health Fund). Through this work, authors approximated concepts such as benefits guaranteed and above‑standard benefits; they also attempted to extract benefits for which it is possible to charge fees, and which, therefore, are not covered by the contract with the Narodowy Fundusz Zdrowia (National Health Fund). In addition, analysis of the problem has been undertaken in respect of the legal entities implementing the provision. The authors also presented a current state of the guaranteed benefits’ supplementary payment system, based largely on vague and very complex regulations and patients unaware of the rights which they are entitled to. In the final section authors present conclusions de lege ferenda, enabling the clarification of co‑financing the benefits’ system and voluntary insurance.

Key words: Narodowy Fundusz Zdrowia (National Health Fund), co‑benefits, benefits guaranteed, above‑standard medical devices.