The aim of this study was to evaluate the one–year prevalence of tension–type headache in the general population. Three thousand men and one thousand women aged 40 years from the Danish population were included. They received a mailed questionnaire and the response rate was 87%. The selfreported one–year prevalence of tension– type headache was 84.7%. The one–year prevalence of infrequent episodic, frequent episodic and chronic tension–type headache was 48.2%, 33.8% and 2.3%, respectively. No tension–type headache and infrequent episodic tension–type headache was significantly more frequent in men than women (
p
<0.0005 and
p
=0.004), while frequent and chronic tension–type headache was significantly more frequent in women than men (
p
<0.0005 and
p
<0.0005). No tension– type headache and infrequent tension–type headache was significantly more frequent among those without than with self–reported migraine (
no headache
, men,
p
<0.0005 and women,
p
=0.002 and
infrequent
, men,
p
<0.0005 and women,
p
<0.0005), while episodic frequent and chronic tension–type headache was significantly more frequent among those with than those without self–reported migraine, with the exception of chronic tension–type in women (
frequent episodic
, men,
p
<0.0005 and women,
p
<0.0005 and
chronic
, men,
p
<0.0005 and women,
p
=0.08). Women are more prone to tensiontype headache than men and they have it more frequently than men. Self–reported migraine increases the risk for frequent episodic and chronic tension–type headache.