Post coronavirus disease-19 (post COVID-19) is mainly studied in clinical populations and less is known about post COVID-19 in a young general population. The aim of the study is to investigate the prevalence and symptoms of post COVID-19 and its potential risk factors in young adults. Participants from the Swedish population-based birth cohort BAMSE were included (n = 2022, mean age 26.5 years). Post COVID-19 was assessed through a questionnaire and defined as symptoms after confirmed COVID-19 (registry-based or self-reported positive test) lasting for ≥ 2 months. In total, 681 participants had had confirmed COVID-19. Among them, 112 (16.5%) fulfilled the definition of post COVID-19 (17.8% in females, 14.5% in males, p = 0.26). The most common post COVID-19 symptoms were altered smell and taste (68.8%), dyspnea (33.7%) and fatigue (30.4%). Overall, no major risk factors for post COVID-19 were identified except for being bedbound during COVID-19. However, asthma and rhinitis were associated with the post COVID-19 symptom dyspnea, migraine with altered smell and taste, and lower self-rated health with fatigue. In conclusion, post COVID-19 symptoms are common, also among young adults in the general population. Although not life-threatening, it could have a considerable impact on public health due to the high prevalence and long-term symptoms.