This study investigates the impact of the extension of the duration of general education on educational opportunities and labour market performance. Taking the example of the Polish education reform of 1999, which we treated as a natural experiment, we used a regression discontinuity design and estimated the effects of an additional year of general education on the relative opportunities for rural and urban children to obtain secondary general, secondary vocational, or tertiary education and on their wages. Although the impact was quantitatively small, a shift towards increased enrolment in general education programmes was observed. Whereas prolonged compulsory education translated to higher wages for basic and secondary vocational school graduates from rural areas, it did not do so, for those from urban areas.