Watching TV has been consistently associated with higher risk of adverse health outcomes, but the effect of other sedentary behaviors (SB) is uncertain. Potential explanations are that watching TV is not a marker of a broader sedentary pattern and that each SB reflects different sociodemographic and health characteristics. Data were taken form a survey on 10,199 individuals, representative of the Spanish population aged ≥18 years. SB and other health behaviors were ascertained using validated questionnaires. Watching TV was the predominant SB (45.4% of the total sitting time), followed by sitting at the computer (22.7%). TV watching time showed no correlation with total time on other SB (r: -0.02, p = 0.07). By contrast, time spent at the computer was directly correlated with time spent on commuting (r: 0.07, p<0.01), listening to music (r: 0.10, p<0.01) and reading (r: 0.08, p<0.01). TV watching time was greater in those with older age, lower education, unhealthier lifestyle, and with diabetes or osteomuscular disease. More time spent at the computer or in commuting was linked to younger age, male gender, higher education and having a sedentary job. In conclusion, watching TV is not correlated with other SB and shows a distinct demographic and lifestyle profile.