IntroductionThe goal of this study was to estimate and to describe the smoking cessation changes in Spain from 1987 to 2020, according to the main sociodemographic characteristics. Material and methodAnalysis of the historical series of the Spanish National Health Survey and the European Health Survey in Spain. Quit rate (QR) was defined as the number of former smokers among the total number of people who are smokers or have smoked at some time in their life. Other included variables were year of survey, age, gender and educational level. Poisson regression models were simultaneously adjusted for sociodemographic characteristics, estimating QR and its 95% confidence intervals (CIs) for each year. ResultsThe absolute difference in standardized QR increased from 1987 to 2017 by 18.6% (95%CI: 16.8-20.4), being moderately higher in men (19.2%; 95%CI: 17.1-21.4) than in women (16.5%; 95%CI: 13.3-19.7). An increase in QR was observed in all age groups, but its magnitude increased with age, estimating a difference in QR between 1987 and 2017 of 22.4% (95%CI: 17.7-27.1) in those aged over 64. People having university studies showed a higher QR during the period, 32.7% (95%CI: 27.5-38.0), especially when compared to those with a lower level of education (9.0%; 95%CI: 4.8-13.2). ConclusionQR has increased sharply and steadily since 1987, however important differences were detected according to age and educational level, highlighting the large increase in inequity observed in these 33years of evolution.