Motions submitted to the Swedish Parliament are important data for social science and humanities researchers. We introduce a new research corpus, the Swedish Parliamentary Motions Corpus, which is larger and more developed than previously available research corpora for the Swedish motions. The corpus contains annotated and structured parliamentary motions over more than 150 years, through the bicameral parliament (1867–1970) and Sweden’s current unicameral parliament (1971–). Along with the corpus, we describe procedures to measure and ensure transparency around issues related to the data quality of the corpus. In addition, we link motions’ authors to a rich metadata set, ensuring the corpus’s utility in various research applications.