Attentional disruption has been demonstrated using laboratory-induced pain, but has not been reliably established in everyday pain conditions. This study is the first to examine the effect of everyday acute headache on attention. Seventy-five frequent headache sufferers completed a flanker task, n-back task, attentional switching task, and dual task. Participants completed this battery of tasks twice: once when experiencing an episode of tension-type headache, and once when pain free. Headache impaired performance on the n-back task, retarded general responding on the flanker task, and produced more errors on the attentional switching task. Headache did not, however, alter performance on the dual task, or the size of the attentional switching effect or result in a flanker effect. It must therefore be emphasised that headache pain appears to impair general task performance, irrespective of task complexity, rather than specific attentional mechanisms. Headache pain has an effect on the core cognitive components necessary for the successful completion of tasks, and in particular those involving the updating of the cognitive system.