We set up an oligopolistic model with two exporting firms selling to a third market to investigate the welfare implications of trade liberalization when the exporting firms are forward‐looking. The results show that with cost asymmetry trade liberalization encourages the exporting firms to engage in tacit collusion, which may not only be detrimental to the domestic welfare, but also to the consumer surplus of the importing country. Moreover, we find that tacit collusion is less sustainable if the government of the importing country imposes a lower (higher) tariff on the more (less) efficient exporting firm. If a nonforward‐looking or a forward‐looking cost‐efficient domestic firm exists in the importing country, then trade liberalization also encourages tacit collusion.