Background Percutaneous endoscopic gastrostomy (PEG) is the method of choice for patients in need of long-term nutritional support or gastric decompression. Although it is considered safe, complications and relatively high mortality rates have been reported. We aimed to identify risk factors for complications and mortality after PEG in routine healthcare. Methods This retrospective study included all adult patients who received a PEG between 2013 and 2019 in Region Norrbotten, Sweden. Results 389 patients were included. The median age was 72 years, 176 (45%) were women and 281 (72%) patients received their PEG due to neurological disease. All-cause mortality was 15% at 30 days and 28% at 90 days. Malignancy as the indication for PEG was associated with increased mortality at 90 days (OR 4.41, 95% CI 2.20–8.88). Other factors significantly associated with increased mortality were older age, female sex, diabetes mellitus, heart failure, lower body mass index and higher C-reactive protein levels. Minor and major complications within 30 days occurred in 11% and 15% of the patients, respectively. Diabetes increased the risk of minor complications (OR 2.61, 95% CI 1.04–6.55), while those aged 75 + years were at an increased risk of major complications, compared to those younger than 65 years (OR 2.23, 95% CI 1.02–4.85). Conclusions The increased risk of death among women and patients with malignancy indicate that these patients could benefit from earlier referral for PEG. Additionally, we found that age, diabetes, heart failure, C-reactive protein and body mass index all impact the risk of adverse outcomes.