The article analyses Spanish and Portuguese verbal periphrases that express the beginning of a process (ingressive manner of action). It analyses stylistically marked and stylistically unmarked ingressive constructions in order to determine similarities and differences between the two languages. The study is primarily based on the comparable web corpora Aranea which makes it possible to see the frequency of use of Spanish and Portuguese periphrases in contemporary language, compare them and determine semantic restrictions for auxiliated verbs in each construction. As a result of this corpus analysis, it is possible to trace the main systemic correspondences between Spanish and Portuguese ingressive verbal periphrases and see the relationship between the original meaning of a concrete semi-auxiliary verb and the group of infinitives that can appear in a periphrasis introduced by that verb.