Atham — August 16, 2026: Atham marks the beginning of the traditional 10-day Onam celebrations. Families start preparing their homes for the festival and create the first Athapoo Pookalam, or floral carpet. The initial design is traditionally simple and becomes more elaborate as the days progress. Atham is also associated with Atthachamayam, a colourful cultural procession held in Kerala to mark the beginning of the Onam season. Nakshatra timing: Atham Nakshatra begins at 3:25 AM on August 16 and ends at 3:50 AM on August 17. (AI photo)

Chithira — August 17, 2026: Chithira is the second day of the traditional 10-day Onam sequence. Families continue cleaning and decorating their homes while adding more flowers and layers to the Pookkalam. The floral design gradually becomes larger and more elaborate as the festival approaches. Nakshatra timing: Chithira Nakshatra begins at 3:50 AM on August 17 and ends at 4:58 AM on August 18. (AI photo)

Chothi — August 18, 2026: Chothi, the third day, brings a stronger festive mood to households. Traditionally, families shop for new clothes, jewellery and other items for loved ones as preparations gather pace. The Pookkalam also becomes brighter and more elaborate with additional flowers. Nakshatra timing: Chothi Nakshatra begins at 4:58 AM on August 18 and ends at 6:46 AM on August 19. (AI photo)

Vishakham — August 19–20, 2026: Vishakham marks an important stage in preparations for the grand Onam feast. Families begin planning and gathering ingredients for Onasadya, while Pookkalam designs become increasingly elaborate. In some communities, preparations for festive activities and competitions also gain momentum. Vishakham is the fourth day of the traditional sequence, but it falls across August 19 and August 20 in the 2026 calendar. Nakshatra timing: Vishakham Nakshatra begins at 6:46 AM on August 19 and ends at 9:08 AM on August 20. (AI photo)

Anizham — August 21, 2026: Anizham is closely associated with Vallam Kali, Kerala’s famous snake boat races. Traditional longboats, known as chundan vallams, become the centre of attention as rowers compete in spectacular races along Kerala’s backwaters. The day also falls during the period when Onam preparations intensify. Nakshatra timing: Anizham Nakshatra begins at 9:08 AM on August 20 and ends at 11:53 AM on August 21. (AI photo)

Thrikketta — August 22, 2026: Thrikketta is the sixth day of the traditional Onam sequence. Families continue decorating their homes, while Pookkalams become larger and more elaborate. Temple visits, family gatherings and community celebrations are also part of Onam traditions during this period. Nakshatra timing: Thrikketta Nakshatra begins at 11:53 AM on August 21 and ends at 2:49 PM on August 22. (AI photo)

Moolam — August 23, 2026: Moolam is the seventh day of the traditional Onam sequence and marks a significant rise in festive activity. In several places, Onasadya begins to be served, including at temples, while traditional performances such as Pulikali and Kaikottikali add to the celebrations. Pookkalams also take on more distinctive forms. Nakshatra timing: Moolam Nakshatra begins at 2:49 PM on August 22 and ends at 5:44 PM on August 23. (AI photo)

Pooradam — August 24, 2026: Pooradam is the eighth day and has a special place in traditional Onam rituals. In some traditions, small figures associated with Mahabali and Vamana, commonly known as Onathappan or Thrikkakara Appan, are placed at the centre of the Pookkalam. Practices can vary across regions and communities. Nakshatra timing: Pooradam Nakshatra begins at 5:44 PM on August 23 and ends at 8:28 PM on August 24. (AI photo)

Uthradam — August 25, 2026: Uthradam is the day before Thiruvonam and is traditionally associated with the final preparations for the festival. It is popularly known as Uthrada Pachil, or the last-minute shopping rush. Families stock up on vegetables, groceries, clothes and other essentials needed for Thiruvonam and the grand Onasadya. Uthradam is also known as First Onam in Kerala’s traditional celebration sequence. Nakshatra timing: Uthradam Nakshatra begins at 8:28 PM on August 24 and ends at 10:51 PM on August 25. (AI photo)

Thiruvonam — August 26, 2026: Thiruvonam is the most important day of the traditional Onam celebration and is observed as Second Onam. In 2026, Thiruvonam falls on Wednesday, August 26. According to tradition, King Mahabali is believed to return to visit his people on this day. Families decorate their homes, prepare an elaborate Onasadya, wear new clothes and come together for prayers, cultural celebrations and feasting. Nakshatra timing: Thiruvonam Nakshatra begins at 10:51 PM on August 25 and ends at 12:48 AM on August 27. (AI photo)

Avittam Third Onam August 27: Although the traditional 10-day celebration from Atham to Thiruvonam culminates on August 26, Kerala’s broader Onam festivities continue with Third Onam and Fourth Onam. Avittam is observed as Third Onam. In 2026, Avittam Nakshatra begins at 12:48 AM on August 27 and ends at 2:15 AM on August 28. Thrissur Pulikali is among the cultural celebrations associated with this period. (AI photo)

Chathayam Fourth Onam August 28: August 28 is observed as Fourth Onam. Chathayam Nakshatra begins at 2:15 AM on August 28 and ends at 3:13 AM on August 29. It also coincides with the Kerala Government’s listing of Fourth Onam alongside Sree Narayana Guru Jayanthi and Ayyankali Jayanthi. (AI photo)