Although tailored interventions consisting of only a few pages of information lead to more quitting than no intervention in the short term, the long-term efficacy of a single tailored intervention still has to be proven. In the present study smokers were reactively recruited and randomly allocated to one of four intervention conditions: (1) outcome information, (2) self-efficacy enhancing information, (3) both sorts of information or (4) no information. Smokers in the three experimental groups received computer-generated tailored feedback containing the condition-specific information, by mail. The results from the 14 months follow-up can be summarized as follows. Compared to the no information condition, all three experimental conditions led to significantly more smokers who had engaged in 24-h quit attempts. However, no experimental condition led to more 7-day quitting than the no information condition. With regard to continuous abstinence, the experimental condition offering a combination of outcome information and self-efficacy enhancing information had a significant effect, compared to the no information condition. It is concluded that a minimal six-page tailored intervention can be beneficial in supporting smokers to quit smoking, even after 14 months.