A brief religious ceremony will be held with relatives of the dead from the incident that killed about 1,000 passengers, as well as residents who got onto the train after the first wave inundated the low-lying area.
Buddhist, Hindu, Christian and Muslim ceremonies will also be held to commemorate victims across the South Asian island nation.
In Thailand, where official figures say more than 5,000 were killed, around half of them foreign tourists, and 3,000 left missing, hundreds of people are expected to attend a government memorial ceremony set for December 26.
Among those invited are representatives of the foreign countries whose tourists made up around 2,500 of the dead.
