Vaisakhi, is the day when Khalsa (the Sovereign One) was unveiled by Guru Gobind Singh. Guru Gobind Singh unveiled the Khalsa through the 'initiation of steel' on 30 March 1699. On this day, celebrations are held in Gurdwaras with Kirtan, Katha, lectures, distribution of Karah Parsad and partaking of Langar. In addition, the Amrit initiation is offered to those who declare themselves ready to lay down their lives for the supremacy of Waheguru's Will. The Sikhs after taking Amrit are called Khalsa. The Amrit ceremony can be held at any other time as well. Vaisakhi is generally celebrated on the 13th April every year. However, its occurence is governed by the Lunar Calendar, called Bikrami Sammat.

Vaisakhi is also celebrated as a seasonal festival in the Punjab. Being closely connected with harvesting, the festival used to be traditionally celebrated as the harbinger of happiness and plenty. Some anthropologists are of the view that to ward off malignant spirits ruinous to the harvest, a ritual dance used to precede the Vaisakhi festivities in olden times. And Bhangra, the world-famous Punjabi dance-form, is said to have evolved from this ritual dancing.

As some Sikh chronicles record, Guru Nanak (1469-1539) was born during the month of Vaisakh. According to Sarup Das Bhalla, (Mahima Prakash, Part 2), Guru Amar Das (1479-1574), at the suggestion of Sikhs led by Bhai Paro, started an annual congregational fair at Goindval on the occasion of Vaisakhi. It became customary for distant Sikh sangats to assemble at the seat of the Guru on every Vaisakhi (and later on Bandi-Chhorh) day. With the inauguration, by Guru Gobind Singh, of the Khalsa on 1 Vaisakh 1756 Bk, Vaisakhi became an important festival on the Sikh calendar. The date then corresponded with 30th March 1699, but owing to the adoption of Gregorian calendar by the British in 1752 and the widening difference between the Christian and the Bikrami years since then, Vaisakhi now usually falls on 13 and sometimes on 14 April.

As stated above, the Sikhs everywhere celebrate Vaisakhi enthusiastically as birth anniversary of the Khalsa. Akhand paths are recited followed by kirtan and ardas in every gurdwara. Langar forms part of the celebrations. At bigger centres congregational fairs, amrit-sanchar, i.e. initiation ceremonies for inducting novitiates into the Khalsa fold, and contests in sports involving test of physical prowess are held. Until the partition of the Punjab in 1947, the largest attended Vaisakhi fairs were those of Panja Sahib, in Attock district, and Eminabad, in Gujranwala (now both in Pakistan). The most important venues now are the Harmandar Sahib, Amritsar, Takht Damdama Sahib at Talvandi Sabo, in Bathinda district, and Takht Kesgarh Sahib, Anandpur Sahib, in Ropar district, all in the Punjab (India). It was at Kesgarh Fort that graduation of Sikhs into the Khalsa through the administration of "khande di pahul", or initiation of the double-edged sword, first took place on the Vaisakhi day of 1699.