Objective. To assess the extent of long-term use of different nicotine replacement treatment products in smokers attending routine smoking cessation treatment and to examine the effect of nicotine replacement treatment cost on its long-term use. Method. 1518 consecutive patients prescribed nicotine replacement treatment at the East London Smokers' Clinic between January 2000 and November 2002 were followed up at 1-year. Results. The rates of long-term use ranged from 2% for patch to 13% for nasal spray. Long-term use of nicotine replacement treatment was significantly more likely in more dependent smokers. Treatment cost, and whether it was provided free of charge, had no significant effect on its long-term use. Conclusions. Long-term use of nicotine replacement treatment is not uncommon. Its occurrence seems positively related to speed of nicotine delivery of individual products. For self-selected highly dependent smokers, long-term use of nicotine replacement treatment may be a necessary precondition for maintaining long-term abstinence. The findings have financial and clinical implications for providers of smoking cessation services. (c) 2006 Published by Elsevier Inc.