ਵਡਭਾਗੀ ਗੁਰ ਕੇ ਸਿਖ ਪਿਆਰੇ ਹਰਿ ਨਿਰਬਾਣੀ ਨਿਰਬਾਣ ਪਦੁ ਪਾਇਆ ॥੨॥
Very fortunate are the beloved Sikhs of the Guru; through the Lord, they attain the supreme state of Nirvana. ||2||
– Sri Guru Granth Sahib Ji: 494

Nirvana, according to Gurmat, is the state where the devotee stays forever in bliss inside his deity – Vaheguru, in Sachkhand. In Siri Jap Jee Sahib, Siri Guru Jee has written about Sach Khand as a tangible (not in the material or corporeal sense) place where Bhagats reside in the presence of Vaheguru. This state of the highest level is different from the Nirvana of Buddhists, which is essentially a state of self-annihilation i.e. state in which the devotee loses all identity. In Gurmat, the devotee gets merged in Vaheguru, but does not get annihilated.