In this paper, we test whether firms that undertake aggressive merger and acquisition (M&A) decisions are likely to be associated with more tax avoidance. Our findings show that firms that engage in M&A perform more tax avoidance than firms that do not make an acquisition announcement. We argue that managers who invest large dollar values in acquisitions are expected to engage in more tax avoidance practices. Using a takeover sample, we determine that highly acquisitive firms exhibit higher tax avoidance activities compared to less acquisitive firms. We also determine that large and frequent acquisition decisions deteriorate firm value in the long run, which is consistent with the view that acquisitive managers implement higher tax avoidance strategies to pursue their self-serving objectives.