This study explored the effects of concurrent group dynamic assessment (G-DA) and cumulative G-DA on Iranian pre-intermediate English as a foreign language (EFL) learners’ interlanguage pragmatic comprehension (ILPC). To this end, a total of 97 pre-intermediate learners took the key English test (KET) test and 45 learners whose scores fell between − 1 and + 1 SD were selected and randomly assigned to experimental groups, namely concurrent G-DA (n = 15), cumulative G-DA (n = 15), and a control group, namely immediate feedback (IF) group (n = 15). Then, they went through pre-test, interventions (lasting fifteen 1-h sessions held three times a week), and post-test procedures, as well as the interactions among the teachers and learners were recorded. The data were analyzed through a one-way analysis of covariance (ANCOVA) and a microgenetic development approach. Results revealed that the concurrent G-DA and cumulative G-DA outperformed the IP group concerning the gains in the ILPC on the post-test. Additionally, the complementary microgenetic findings demonstrated the ways through which the concurrent G-DA and cumulative G-DA could lead to improving the learners’ ILPC.