Patient satisfaction surveys are increasingly used for benchmarking purposes. In the Netherlands, the results of these surveys are reported at the univariate level without taking case mix factors into account. The first objective of the present study was to determine whether differences in patient satisfaction are attributed to the hospital, department or patient characteristics. Our second aim was to investigate which case mix variables could be taken into account when satisfaction surveys are carried out for benchmarking purposes. Patients who either were discharged from eight academic and fourteen general Dutch hospitals or visited the outpatient departments of the same hospitals in 2005 participated in cross-sectional satisfaction surveys. Satisfaction was measured on six dimensions of care and one general dimension. We used multilevel analysis to estimate the proportion of variance in satisfaction scores determined by the hospital and department levels by calculating intra-class correlation coefficients (ICCs). Hospital size, hospital type, population density and response rate are four case mix variables we investigated at the hospital level. We also measured the effects of patient characteristics (gender, age, education, health status, and mother language) on satisfaction. We found ICCs on hospital and department levels ranging from 0% to 4% for all dimensions. This means that only a minor part of the variance in patient satisfaction scores is attributed to the hospital and department levels. Although all patient characteristics had some statistically significant influence on patient satisfaction, age, health status and education appeared to be the most important determinants of patient satisfaction and could be considered for case mix correction. Gender, mother language, hospital type, hospital size, population density and response rate seemed to be less important determinants. The explained variance of the patient and hospital characteristics ranged from 3% to 5% for the different dimensions. Our conclusions are, first, that a substantial part of the variance is on the patient level, while only a minor part of the variance is at the hospital and department levels. Second, patient satisfaction outcomes in the Netherlands can be corrected by the case mix variables age, health status and education. © 2009 Elsevier Ltd. All rights reserved.