In this paper, we assess whether trade among member countries of a regional trade agreement (intra-regional trade) contributes more to output growth than trade with nonmember countries (extra-regional trade). We use Granger causality tests to evaluate the trade-growth relationship in 13 countries from the European Union and separately estimate the differential impact of the two kinds of trade on economic growth over the period 1980-2003. In addition to the basic influences of investment and population growth, we find that intra-regional trade has had a lesser impact on growth in output per capita than extra-regional trade by almost 30%.• JEL classification: F13, F43, C33 *Corresponding address: Rossitza B. Wooster;