This paper explores the link between speaker background and language attitudes, self-confidence in language abilities and use of Welsh in participants from two Welsh medium Sixth Form units in a Welsh-prevailing North West Wales region and an English-prevailing North East Wales region. Youth from English-speaking homes feel less assured in their Welsh and their Welsh use is rather low in both regions. Amongst youth from Welsh-speaking homes, use is significantly lower in the North East region, due to peer-group dynamics: in the North West, language-particular peer groups existed, whilst English constituted the language of all North Eastern peer groups.