The article considers how the principle of good faith of the participants of civil law-based transactions enshrined in Article 1 of the Russian Civil Code affects the rules of notarial certification. The function of legal advising requires the notary to know the standards of good faith for various commodity markets and to explain them to the parties entering into a transaction, so that the parties would not be blamed for non-compliance in future legal disputes. The notary procedure’s formalism, which does not take into account the principle of good faith, should become a thing of the past. Notary rules should be synchronised with substantive law in such a way that the notary is not obliged to certify a transaction in case of obviously unfair behaviour by the parties.