Objective: The prevalence of post-COVID-19 Syndrome (PCS) is estimated to be between 10% and 20%. The main reported symptoms are fatigue, memory alterations, dyspnea, sleep disorders, arthralgia, anxiety, taste alterations, coughing and depression. The main goal of our study was to determine the prevalence of post-COVID-19 symptoms within a group of Colombian patients who were recruited during their outpatient appointments. Methodology: Cross-sectional study conducted between December 2021 and May 2022. 1047 adults nationwide were included. The participants reported post-COVID-19 symptoms during 12+ weeks after the infection by SARS-Cov-2 was first documented via RT-PCR testing. Results: The median age was 46.63% of the patients were women. 41% of the patients had a pre- existing chronic condition prior to COVID-19, such as hypertension, anxiety disorders, diabetes, hypothyroidism, obesity, and asthma. Only 22% of the patients had received at least the first dose of the vaccine against the virus. The more prevalent symptoms within our group are described as follows: fatigue (53.3%), dyspnea (40.3%), arthralgia and/or myalgia (43%), cephalea (40.5%), sleep disorders (35.7%) and coughing (31.3%). 72% of the patients presented four or more post-COVID 19 symptoms, 9% two symptoms, and 10% only one symptom.Conclusion: Behavior of the PCS in the participants was similar to that of local and international evidence. PCS could have a complex diagnosis given its pathophysiological characteristics and frequent multisystemic affectation.Funding: Tecnoquímicas finances any publication costs, if applicable. However, it is important to note that this study does not involve any molecules or products from Tecnoquímicas. Its sole purpose is to bridge the knowledge gap regarding long COVID in the adult Colombian population.Declaration of Interest: None.Ethical Approval: This study was considered low risk. Each participant signed an informed consent form prior to their engagement and their information was gathered abiding by data collection standards as per Colombian law. This study was approved by the ethical committee CAYRE, and the researchers adhered to good clinical research practices (GCP), national and international regulations as well as the declaration of Helsinki.