They can be broadly divided into two denominations: Iyengars, who are adherents of Sri Vaishnavism, and Iyers, who follow the Srauta and Smarta traditions.

[1][2] Their community was mainly strengthened by the more recent settlement of Tamil Brahmins from the Iyer caste in Sri Lanka, mostly from the second half of the 18th century.

They are concentrated mainly along the Cauvery Delta districts of Nagapattinam, Thanjavur, Tiruvarur and Tiruchirapalli where they form almost 10% of the total population.

[5][6][7] They are also found in significant numbers in Chennai,[8] Coimbatore, Madurai, Thiruchirappalli, Thanjavur, Palakkad, Alappuzha, Kozhikode, Ernakulam, Kannur, and Thiruvananthapuram.

[10] Brahmins who serve as priests in temples following the Vaishnavite and Shaivite tradition and perform pujas are offered a distinct category classified outside the community by the Government of Tamil Nadu as '703.Adi Saivar' and '754.Saiva Sivachariyar' as distinct from the '713.Brahmanar' (Brahmin) in the list of forward castes.