To review the etiology, precipitating factors, clinical findings, screening recommendations, and treatment for primary hypothyroidism and subclinical hypothyroidism in the older patient.A PubMed search of English language articles using a combination of words: elderly, thyroid, hypothyroid,* subclinical hypothyroid,* etiology, screening, diagnosis, and treatment to identify original studies, guidelines, and reviews on primary hypothyroidism and subclinical hypothyroidism published between 1979 and present.Overall, 51 clinical reviews, original studies, references, and guidelines were obtained and evaluated on their clinical relevance to the older patient population.The literature included guidelines and considerations for the diagnosis, screening, and management of subclinical and overt primary hypothyroidism in the older patient.Females and individuals 60 years of age or older have a higher prevalence of primary hypothyroidism and subclinical hypothyroidism. While screening recommendations exist, the need or suggested age to initiate screening varies among organizations. TSH and free T4 values are used for diagnosing and monitoring. Levothyroxine remains the drug of choice for replacing endogenous thyroid hormone. Despite evidence to suggest its need, the treatment of subclinical hypothyroidism remains controversial.