Oral semaglutide provides an alternative to injectable glucagon-like peptide-1 receptor agonists (GLP-1RAs) for treatment of type 2 diabetes (T2D). The PIONEER REAL studies evaluate clinical outcomes of oral semaglutide treatment of T2D in a real-world setting. PIONEER REAL UK focused on adults living with T2D in the UK. The multi-centre, prospective and non-interventional single-arm study enrolled 333 participants and followed them for 34-44 weeks. Participants were treated as part of routine clinical practice and had not been previously treated with injectable glucose-lowering medication. The primary endpoint was change in glycated haemoglobin (HbA1C) from baseline to end of study (EOS). Secondary endpoints included change in body weight, proportion of participants with HbA1C < 7% (53 mmol/mol) at EOS and proportion of participants with ≥ 1%-point HbA1C reduction and body weight reduction of ≥ 3% or ≥ 5% at EOS. Treatment satisfaction was assessed by Diabetes Treatment Satisfaction Questionnaire (DTSQ) status and change. Of 333 participants, 299 completed the study and 227 were on treatment at EOS. People treated with oral semaglutide experienced significantly reduced HbA1C by an estimated change of - 1.1%-points (95% CI - 1.27 to - 0.96; P < 0.0001) or - 12.2 mmol/mol (CI - 13.87 to - 10.47; P < 0.0001). Estimated change in body weight was - 4.8 kg (CI - 5.47 to - 4.12; P < 0.0001). At EOS, an HbA1C level < 7% (53 mmol/mol) was recorded in 46.3% of participants. A ≥ 1%-point reduction in HbA1C combined with a ≥ 3% reduction in body weight was observed in 36.4% of participants, and 27.1% had a ≥ 1%-point reduction in HbA1C and a ≥ 5% body weight reduction. Treatment satisfaction improved significantly during the study. No new safety concerns or cases of severe hypoglycaemia were reported. People living with T2D in the UK experienced a meaningful decrease in HbA1C and body weight after initiation of oral semaglutide treatment. No new safety issues were observed. ClinicalTrials.gov: NCT04862923. Graphical plain language summary available for this article.