In view of the need to define the areas of further improvement of the mechanism of levying single social contribution (SSC), considering the challenges and threats stemming from the increasing deficit of the Pension Fund of Ukraine, an analysis of reforms of the said contribution implemented during 2015—2017 in the context of their effect on the degree of shadowization of wage payments in the country becomes especially important.The scientific rationale for the expediency of lowering the SSC rate in order to reduce the degree of shadowization of wage payments was analyzed. The reform of SSC in Ukraine in 2016 was assessed in the context of its effect on the degree of shadowization of wage payments and unofficial employment, which gave reasons to conclude that no significant positive effects were produced by the said reform. An insignificant decline of these indicators is incomparable with the adverse consequences which this reform had for revenues of the Pension Fund of Ukraine. Calculations of tax burden on the wages paid in Ukraine in 2010—2019 were made. It was established that in 2016, tax burden on payroll fund declined to 28,58% versus 2015, but the following years saw an insignificant growth of this indicator to 30,16% in 2019. It was proved that the drastic lowering of the SSC rate did not stimulate employers to deshadowize wages. For when Ukrainian lawmakers initiated this reform, they failed to take into account a number of nontax factors in deshadowization of wage payments related, in particular, to the quality of Ukrainian legislation and regulatory policy and to the level of corruption in the country. Given that employers remain able to conceal the actual number of personnel and the amount of their wages, it will be impossible to solve the problem of unofficial employment and shadowization of wage payments only by lowering the SSC rate. An emphasis was placed on the need to apply a systemic approach to the assessment of possible consequences from future transformations of SSC and their impact on tax burden on payroll fund in terms of all its components and taking into account nontax factors in deshadowization of wage payments.