Amrit Sanskar (Punjabi: ਅੰਮ੍ਰਿਤ ਸੰਸਕਾਰ, romanized: Amrita sansakāra, pronunciation: [ãːmɾʱɪt̪ sә̃nskäːɚ], lit. "nectar ceremony") is one of the four Sikh Sanskars. The Amrit Sanskar is the initiation rite introduced by Guru Gobind Singh when he founded the Khalsa in 1699.

A Sikh who has been initiated into the Khalsa ('pure'; the Sikh brotherhood) is considered to be Amritdhari (baptised) (lit. 'amrit taker') or Khalsa ('pure'). Those who undergo initiation are expected to dedicate themselves to Waheguru (Almighty God) and work toward the establishment of the Khalsa Raj.

The Amrit Sanskar ceremony has many alternative names, such as Amrit Parchar, Amrit Sanchar, Khande di Pahul, Khande Batte di Pahul (Punjabi: ਖੰਡੇ ਬਾਟੇ ਦੀ ਪਾਹੁਲ, romanized: Khaḍē bāṭē dī pāhula), or khande-baate da amrit.

The original Sikh initiation ceremony, ever since the guruship period of Guru Nanak, was known as Charan-Pahul (Punjabi: ਚਰਨ-ਪਾਹੁਲ, romanized: Carana-pāhula), Pagpahul, or Charan Amrit (Punjabi: ਚਰਨਾਮ੍ਰਿਤ, romanized: Caranāmrita, lit. 'elixir of the feet'). It involved pouring water over the toes of the Sikh guru and the initiates drinking that water. If the guru was not present in a certain area, water would be poured over the toes of the masand or sangatia responsible for the area of that particular manji (early Sikh religious administrative unit) and the initiates would drink that water instead. If neither the guru or a local religious head is present, such as in a distant or tiny community of Sikhs, then the initiate would dip their toe in water and the local congregation would drink it. This initiation ceremony finds mention in the Vaaran authored by Bhai Gurdas. The ceremony was a way of showing the humbleness of initiates to the faith. This practice continued until 1699, when it was replaced by Guru Gobind Singh's innovation.

According to the Dabestan-e Mazaheb, the 'sahlang' term referred to person(s) initiated into the Sikh religion by a masand, who acted as representatives on behalf of the Sikh gurus. Such Sikhs were termed as meli or masandia, and were differentiated from Sikhs who had received their initiation rites directly from a Sikh guru, whom were termed as Khalsa.

Amrit Sanchar was formally initiated in 1699 when Gobind Singh established the order of the Khalsa at Anandpur Sahib. The day is now celebrated as Vaisakhi. This tradition had come to replace the prior Sikh initiation ceremony, in which the initiate would drink water that the Guru or a masand (designated official representing the Guru) had dipped his foot in.

Guru Gobind Singh addressed the congregation from the entryway of a tent pitched on a hill (now called Kesgarh Sahib). He drew his sword and asked for a volunteer who was willing to sacrifice his head. No one answered his first call, nor the second call, but on the third invitation, a man by the name of Daya Ram (later to be known as Daya Singh) came forward and offered his head to the Guru. Guru Gobind Singh took the volunteer inside the tent, and emerged shortly, with blood dripping from his sword. The Guru then demanded another head. One more volunteer came forward, and entered the tent with him. The Guru again emerged with blood on his sword. This happened three more times. Then the five volunteers came out of the tent unharmed. Everyone was very confused.

The Guru caused his five faithful Sikhs to stand up. He put pure water into an iron vessel and stirred it with a khanda or two edged sword. He then repeated over it the sacred verses which he appointed for the ceremony, namely, the Japji, the Jaap, Guru Amar Das's Anand, Chopai Sahib and Twe Parsad Swaiyas or quatrains of his own composition.