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Insomnia is common health complaint in primary care and has long-term consequences regarding cognitive functioning and several somatic disorders. Insomnia is also linked to depression and anxiety, as well as somatization. However, the relationship between single somatic symptoms and insomnia is still not well understood. The aims of this study were to identify which specific somatic symptoms of relevance for somatization are associated with being at risk for insomnia when controlled for depression and anxiety in a general Swedish population. This study also investigates whether somatic symptoms associate differently to different aspects of insomnia. Cross-sectional data from 3204 participants (1792 women and 1412 men) gathered by the Västerbotten Environmental Health Study was used. The participants were grouped into a risk and reference group based on prevalence of insomnia reported using the Karolinska Sleep Questionnaire (KSQ). For somatic symptoms the Patient Health Questionnaire-15 (PHQ-15) was used. The somatic symptoms that were most strongly associated with insomnia were in descending order: stomach pain; back pain; nausea, gas or indigestion; dizziness; and constipation loose bowels or diarrhea. Each somatic symptom was associated with a significantly increased risk for insomnia after controlling for depression and anxiety. The study argues that there is no discernible reason for dividing insomnia into subscales when investigating its association to somatic symptoms. The findings are discussed in relation to previous research concerning the link between somatization and insomnia. Future research should investigate if insomnia causes somatic symptoms or vice versa.