Dogs are susceptible to the currently circulating highly pathogenic avian influenza (HPAI) H5 and human H1N1pdm2009 (pandemic H1N1) viruses, yet little is known about the extent to which dogs are exposed to both these viruses. Here we investigated HPAI H5 and human H1N1pdm2009 virus exposure in domestic dogs–including dogs that participated in hunting-training–and investigated lifestyle factors associated with HPAI H5 virus exposure. We screened sera from 538 dogs, sampled between 2021 and 2023, for influenza A virus antibodies, using ELISA and hemagglutination inhibition assays (HAIs). We analyzed lung tissue and (naso)pharyngeal swabs for influenza A viruses using RT-qPCR. Seropositivity to HPAI H5 virus was more frequent (13.3 %) in hunting-training dogs than in companion dogs with unknown bird contact (3.7 %). In contrast, seropositivity to H1N1pdm2009 was more frequent in companion dogs (7.1 %) than in hunting-training dogs (0.7 %). Based on owner questionnaires, seropositivity to HPAI H5 by ELISA in hunting-training dogs was significantly associated with recent bird contact in/near water (odds ratio 6.9). No influenza A viruses were detected in 207 necropsy dogs and 180 (hunting) dogs. Our findings suggest that dogs are frequently exposed to zoonotic influenza A viruses, and we recommend dog owners to avoid dog contact with sick/dead birds.