Peroral endoscopic myotomy (POEM) is an established treatment for primary achalasia. It has gained endorsement from the American Society for Gastrointestinal Endoscopy with increasing clinical acceptance since the first procedure, performed in Japan in 2008. The first successful POEM in the UK was performed in November 2013 at King’s College Hospital and this article presents the first UK case series. Prospective data were collected at 3 and 12–24 months for consecutive patients undergoing POEM. Post-POEM gastro-oesophageal reflux health-related quality of life scale (GORD-HRQoL) score was recorded. Statistical comparisons were made using paired non-parametric testing. In an initial series of 33 consecutive prospectively followed patients (12 female; 49.5±13 years; median follow-up 9 (3–28) months; 58% having had previous intervention), a 91% success rate has been achieved at 3 months. To date, 16 patients have reached the 12-month time point, with 13 (81%) sustaining response. This case series compares well with international cohorts and demonstrates excellent long-term safety and favourable efficacy.