Casay is a barangay (village) in Anini-y, Antique, Philippines. It is located 10 kilometers east of Anini-y town. Located between the barangays of Mabuyong in the west and Iba and Casay Viejo (old Casay, former part of Casay but later it was separated and was recognized as a new barangay) in the northeast. At the east and south is the seashore overlooking the Negros Island, Sipalay and the vast Sulu Sea. And at the north is Igpalge and Milagrosa (formerly Igbarabatuan). Visitors from other provinces often mistook Casay for a town, when in fact it is just a barangay. Part of the reason is the unique beauty and location of the place. Indeed, Casay is a scenic place located between the Sulu sea and the mountains of southern Antique. A congressman once referred to Casay as a "showcase Barangay of Antique".
There is another barangay created and named after Casay, the barangay of New Casay, in the municipality of Braulio E. Dujali, Davao del Norte Province in Mindanao, whose residents include, among others, former Casay residents and those from the neighboring barangays under the Parish of St. Therese of Avila of Casay and from other towns in Antique Province. It used to be that New Casay also celebrates its barangay fiesta in honor of St. Therese of Avila every October 15.
Casay took its name from a large number of trees that grew there which is called casay, though casay trees can now only be sparingly seen in the area.
The people of Casay are called "Casaynons". They are mostly friendly, jolly, religious, and courteous, especially to visitors. The people are predominantly Christians and are genuinely proud of their Roman Catholic heritage. Casay has a good number of professionals and OFWs (overseas Filipino workers) consisted mostly of seafarers, domestic helpers, carpenters, etc. Almost every household has a member who is an OFW. Literacy rate is high as Casay has an elementary school and a private (Catholic) high school, the St. Therese's High School. Most common industry is farming and fishing, including milkfish fry-catching during summer.
Casay holds an annual fiesta for the patron saint, St. Therese of Avila, Doctor of the Church, on the 15th of October, but celebration starts on the 13th of October.
The Parish of St. Therese of Avila was founded in 1901, by the St. Joseph's Missionary Society, also known as the Mill Hill Missionaries (MHM). Among them, was the late Fr. Antonio Smale, MHM (who died in the same year and buried inside the parish church near the altar). It celebrated the 100th year as a parish on the 10th of May 2006.