This paper tests the pro‐competitive effect of imports on product and labour markets for Spanish manufacturing firms in the period 1990–2005. In doing so, it takes into account the type of imported products: final versus intermediate. Markups are estimated following the procedure suggested by Roeger and including an efficient bargaining model. The observed heterogeneity among firms is parametised to consider additional product standardisation and market concentration. The results support the imports as market discipline hypothesis for importers of final goods, while firms that offshore intermediate inputs show similar markups to nonimporters. Additionally, the union bargaining power is smaller for importers and the more homogeneous is the type of goods elaborated by firms.