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Introduction Asthma diagnosis requires a suggestive clinical history alongside objective testing. Current NICE guidance - NG 245 (2024), recommends measurement of fractional exhaled nitric oxide (FeNO) or blood eosinophils as an initial investigation in adults, with spirometry and bronchodilator reversibility reserved for cases where diagnosis remains uncertain. 1 In August 2025, a FeNO-led diagnostic pathway was introduced across community clinics to streamline assessment and reduce unnecessary spirometry.Methods A retrospective audit was conducted of patients referred for FeNO testing between 04/08/2025 and 30/01/2026 across five community sites. Data collected included age, gender, clinic location, FeNO result, spirometry and bronchodilator response (where performed), and technical quality.Results A total of 467 patients were included (mean age 50.7 years, range 13–87; 59% female, 41% male). No exclusion criteria applied.FeNO was successfully obtained in 460 patients (98.5%). Where distribution was:<25 ppb: 262 (57%)25–49 ppb: 110 (24%)≥50 ppb: 88 (19%)Patients with FeNO ≥50 ppb (19%) required no further testing in accordance with NICE (2024) guidance.The remaining 379 patients (81%) were referred for spirometry and bronchodilator reversibility. At time of analysis, spirometry had been completed in 232/379 (61%), 147 (39%) were awaiting appointments and were excluded from further analysis of spirometry/ reversibility outcomes.Of completed tests (N = 232), 169 (73%) were technically acceptable and 63 (27%) unacceptable, predominantly due to poor technique (97%).Among acceptable tests (N=169), significant bronchodilator response (≥12% and ≥200 mL increase in FEV1) was demonstrated in 13 patients (7.7%), with no significant response in 156 (92.3%).Conclusion A FeNO-led diagnostic pathway is feasible within community respiratory clinics, with high completion rates. Nearly one-fifth of patients avoided further lung function testing. However, spirometry demand remained substantial, with notable technical limitations and low bronchodilator reversibility yield. Targeted use of spirometry in line with NICE guidance, such as initial baseline forced spirometry alongside FeNO testing, may improve efficiency and reduce service burden. Reaudit following pathway refinement is warranted.Reference National institute of Health and Care excellence (NICE). Overview | Asthma Pathway (BTS, NICE, SIGN) | Guidance | NICE, 2024. [online] Nice.org.uk. Available at: https://www.nice.org.uk/guidance/ng244.