Onam - the state festival of Kerala - is celebrated with great enthusiasm. The festive season of Onam, which falls on the Malayalam month of Chingam, every year (between August and September), is a ten-day carnival for the Malayalees all over the state, country and abroad. Being a harvest festival, it is time to thank God for the bountiful yield. According to the stories in Hindu epics, Mahabali, the legendary King of Kerala, visits the state every year during the Onam festival, to ensure the wellbeing of the people. He is welcomed to his kingdom with reverence. The festival is all about relishing on the grand Onasadya (traditional feast of Onam), shopping, family reunion and welcoming King Mahabali by spreading good cheer.

A number of rituals are performed during the ten days of Onam, which starts on the Attam nakshatram of Chingam. Rituals such as Maveli Puja, Onathallu, Onakazhcha are rooted in the ancient legends and are followed in many parts of the state, since a long time. Apart from the rituals, enthralling games are played during the ten days, wherein small children, men and women take part with equal enthusiasm. Games such as 'Thumbi Thullal (folk dance performed by women), Kaikotti Kali, Pulikkali form a prominent part of the celebrations of Onam. In addition to this, sporting events such as Uthratadhi Vallamkali (snake boat race) are organized with zeal.

Onasadya is an inevitable part of Onam festival. Thiruvonam is the important day of Onam, wherein the lavish feast is organized. Lip-smacking recipes are prepared by the women in every Malayalee household. Intricate designs of 'rangolis' (with colored rice paste) and 'pookkalam' (with flowers) in front of the homes. There is a tradition of bestowing Onakkodi (new clothes especially purchased for Onam) upon the younger members of family by the elder ones. All the traditions and rituals of Onam attract thousands of tourists from across the country and the world, to Kerala, during the festival of Onam.