ENThis article analyses 33 phrasemes used in the Northern Borderland variety of Polish, which were extracted from about 20 novellas submitted to the competition announced in 1936 by Dzień Polski [The Polish Day], a Polish daily issued in Kaunas. The study classifies the extracted multiword units into substrate-interference units (formed under the infuence of the Belarusian-Lithuanian substrate and more recent interference from Russian and Lithuanian) and archaic-innovative units (outdated and modified without foreign infuence). The descriptions of individual phrasemes follow a standardised pattern. Substrate-interference phrasemes account for 70 % of the material (9 substrate phrasemes, e.g. wiatry w głowie or durzyć głowę, and 14 interference phrasemes, mainly of Russian origin, e.g. jak na zło or podać prośbę), and 30 % are native units (8 obsolete, e.g. zakasać ręce or beczka łoju = góra sadła, 1 local innovation: wyrządzić scenę zazdrości, and 1 phraseme common to indigenous Polish dialects: mieć gdziesik). The phrasematics of the Kaunas novellas makes an addition to the still modest list of multiword units in the Northern Borderland variety of Polish. Keywords: phrasematics of Kaunas novellas; substrate-interference and archaic-innovative phrasemes. [From the publication]