This quantitative study examined the scale, nature and effectiveness of private supplementary tutoring (PT) at one of the transition points in Kazakhstan's education system during the COVID-19 pandemic. The data were collected from 366 secondary school students. The findings show that 73.8% of participants received PT, mainly to help them prepare for the university entrance examination. Seventy-four percent of fathers and 83% of mothers were holders of university degrees and they had the economic means to invest in more and better PT for their children. Thus, PT has the potential to be a force for reducing equity, and so effective policies to regulate PT should be adopted.