Attukal Pongala (Attukal Ponkala) is the most reputed festival of this temple, which attracts devotees from all parts of India. Tens of hundreds of women devotees throng together on the day of Pongala with their offerings to the Goddess and to seek blessings. The festival commences on Karthika day of Malayalam month Makaram-Kumbham (February-March).
Pongala festival is a ten-day long festival and on the 9th day of the festival is the famous Pongala. On that day, tens of hundreds of women throng to the temple to offer pongala in earthen pots. Pongala is a rice porridge, which boils over. The rush of women is so intense that the Pongala ground spreads outside the temple premises and into the public roads, and the courtyards of houses, government offices, bus and train station, etc...
Women offer pongala in a radius of about 7 Km, essentially turning the whole of Thiruvananthapuram City into the holy grounds for the women to offer Pongala. All the transport buses plying from the city are reserved for women on Pongala day. No number of words can do justice to frenzy of the day's festivities, which wholly belongs to women devotees.
The Attukal Pongala festival also reached Guinness Book of World Records of largest annual gathering of women, when 1.5 million (15 Lakhs) women offered pongala in February 23, 1997 and its achieved by 2.5 million (25 Lakhs) women offered pongala on March 10, 2009. It is estimated that about 3.7 million (37 Lakhs) women offered pongala in February 26, 2013. The number of women devotees reaching this place increases every year.
Other activities during the ten-day festival include various ceremonial rituals like Kappukettu, during which the story of Goddess Kannagi (Kannaki) is recited. It is a musical recitation and goes on for the first nine days of the festival. The musical recitation of Kannagi's story ends with the part of the Goddess annihilating the Pandya King. The story signifies victory of good over evil, light over darkness and justice over injustice. Immediately after the end of the recitation, it begins the rituals for Attukal Pongala, which begins with making fire in the temple hearth known as Pandara Aduppu. The fire will then be passed to the women ready to offer pongala and the same fire spreads to all the tens of thousands of women, who are offering pongala.
Kuthiyottam is a ritual performed by boys below the age of 13 years on the pongala day. These boys observe a seven-day Kuthiyotta Vritham (penance), starting third day of the festival. The penance includes staying at the temple, sleeping on the floor, strict diet restrictions, bathing three times a day, etc. The boys also have to bow before the Goddess 1008 times, after morning and evening oblations. These boys represent the wounded soldiers of Goddess Mahishasura Mardini.
Thalappoli is a ritual is performed by girls on the ninth day (pongala day) of the festival. The young girls attired in traditional dressing hold a thaalam (a round tray) with flowers, a lighted oil lamp, and offerings to the Goddess. The Goddess will be pleased on the girls and bless them with beauty, wisdom, health, wealth and joy.
The Kuthiyottam boys accompany the Deity on a grand procession to the Sastha Temple at Manacaud, very early in the morning. The procession is a grand affair with devotees thronging either side of the road, welcoming the procession in gaiety and festival fervor. After short poojas at the Sastha Temple, Deity returns to Attukal, where the temple priest receives the Goddess to perform morning poojas. The boys taken part in Kuthiyottam are delivered penance. At night, the ten day long festival concludes with Kuruthi Tharpanam, a pooja.