Antibiotic resistance is a key factor in the failure of Helicobacter pylori eradication therapy, yet few sentinel schemes exist to monitor trends in resistance at local, national or international levels. This study aimed, over a six-year period, to monitor resistance levels of H. pylori in England and Wales to the four antibiotics used in its treatment. A total of 1,310 isolates from Gwynedd in north Wales and from mid-Essex in south-east England were collected from 2000 to 2005 and tested for susceptibilities to metronidazole, clarithromycin, amoxicillin and tetracycline. Overall, metronidazole and clarithromycin resistance rates were 28.6% and 8.3% in Gwynedd and significantly higher (36.3%, p=0.0031, and 12.7%, p=0.0112) in mid-Essex. Rates of resistance to metronidazole and clarithromycin increased in both areas over this six-year period. Resistance rates were higher in female compared with male patients (38.1% vs 26.6% for metronidazole, p<0.0001, and 12.9% vs 7.5% for clarithromycin, p=0.0024), and were higher in patients <45 years compared with those ?45 years (44.0% vs 29.0% for metronidazole, p=0.0002, and 15.0% vs 9.4% for clarithromycin, p=0.0233). This study highlights the importance of antibiotic resistance surveillance in H. pylori for providing information on local resistance rates for test and treat strategies.