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Introduction Type I gastric neuroendocrine tumours (gNETs) are typically indolent with excellent prognosis and low metastatic risk. However, optimal management remains controversial, particularly for small lesions, with discordant recommendations between UKINETS and ENETS regarding size thresholds for endoscopic resection (ER). Given emerging evidence suggesting that intervention may not prevent recurrence, we evaluated real-world outcomes of ER and explored whether resection modifies disease behaviour.Methods We performed a retrospective study of all patients with histologically confirmed Type I gNETs diagnosed between August 2014 and November 2025 at a UK tertiary centre. Demographic, endoscopic, histological, management and follow-up data were collected. Outcomes included recurrence or persistence, disease progression, complications and adherence to guideline recommendations. Endoscopic and histological tumour size measurements were compared. For patients undergoing ER, outcomes following endoscopic mucosal resection (EMR) were analysed, including safety, completeness of resection (R0), recurrence and predictors of recurrence. EMR techniques (Duette vs inject & snare) were compared with Fisher’s exact test.Results 38 patients were identified with median follow-up of 34.9 months (range 0-114). Tumours were predominantly small (30.3% < 5mm) and low-grade (78.4% Grade 1). Management comprised surveillance alone (n=6), EMR (n=24) and other (n=8, including best supportive care, surgery [n=1] and ESD [n=2]). EMR techniques used included multiband mucosectomy (MBM; n = 18) and inject & snare (n = 6). There were no instances of metastatic progression and no disease-specific mortality. In resected cases, endoscopic assessment overestimated tumour size compared with histology (mean difference 3.2mm). Lymphovascular invasion (LVI) was seen in 14.8% of cases. EMR carried a complication rate of 4.2% (1 case of delayed bleeding) and no cases of perforation. En-bloc and R0 resection rates were 75.0% and 55.0%, respectively. Local recurrence on the EMR site was observed in 23.5% of cases. MBM was superior to inject & snare technique achieving higher R0 resection rate (71.4% vs 0%; p<0.05) and numerically lower local recurrence rate (16.7% vs 40%; p>0.05).Conclusion This study highlights that Type I gNETs demonstrate an indolent clinical behaviour with minimal progression risk even in the presence of LVI. When endoscopic resection is elected, MBM must be preferred over inject & snare as it ensures higher R0 resection rate while carrying a low risk of complication. For small gNETs of a few mm, surveillance appears to be an adequate management strategy. Larger multicentre prospective studies and randomised controlled trials are needed to confirm these findings and validate the best approach to manage type I gNETs.