Tension headaches are typically experienced as a bilateral pressure or tightening sensation in the occipital or frontal region. The pain level is generally mild to moderate in intensity and it is not aggravated by physical activity (kinesophobia). In contrast to migraine, nausea and photophobia are typically mild or absent. Some patients can experience increased head tenderness with manual palpation. Headache duration can last anywhere from 30 minutes to several days, but they are usually several hours in duration.

Tension headaches can be characterized as episodic or chronic. Infrequent episodic tension headaches occur on average once per month or less. Frequent episodic tension headaches occur more than once per month but less than 15 days per month. If tension headaches occur more frequently than 15 days per month, they are categorized as chronic tension headaches.

Tension headaches are the most common type of headache. Episodic tension headaches are common, occurring in 30%-78% of the population. Chronic tension headaches are less common, with a prevalence of about 2% of the population. Tension headaches occur slightly more frequently in females, with a female-to-male prevalence ratio of 1.16 to 1.

The pathogenesis of tension headaches is not fully known. One theory is that tension headache patients experience increased central sensitization to pain. Another theory is that increased sensitivity of myofascial nociceptors in the periphery may contribute to development of tension headaches. Changes in stress or sleep patterns may trigger tension headaches.