In Srimad Bhagavatam, Sri Prahlad Maharaj talks about the nine processes of bhakti, called nava vidha bhakti.

śravaṇaṁ kīrtanaṁ viṣṇoḥ
smaraṇaṁ pāda-sevanam
arcanaṁ vandanaṁ dāsyaṁ
sakhyam ātma-nivedanam     .

…. (S.B. 7.5.23)

“The nine processes of bhakti are: Hearing, chanting (and kirtanam), remembering, serving, worshiping, offering prayers, being a servant, being dear, and offering one’s soul to the Lord.”

However, there are intricate truths inside each of them. Devotees can adapt to any or all of these processes to obtain perfection. For sravanam the acharya is said to be Parikshit maharaja because he heard (or drank) Srimad Bhagavatam without sleeping, eating or even drinking any drop of water for 7 days and nights. The acharya of kirtanam is said to be Srila Sukadeva Goswami who narrated Srimad Bhagavatam. For smaranam, bhakta prahlad is the topmost. For pada sevanam, Maha Lakshmi is the topmost and for archanam, Ambarisha Maharaj is said to be the topmost. For vandanam, Akrura is said to be the topmost, and Hanuman is the topmost for dasyam. While Pandavas, especially Arjuna, are the topmost in sakhya, gopis are the topmost for atma nivedanam because they gave everything to Krishna.

In this blog, the question is that is there any difference between Nama Sankirtan and Hari Katha. We see that Srila Sukadeva Goswami is the acharya of Kirtan. Normally people think that kirtan means only nama sankirtan and the acharya of kirtan will be the acharya of hari nama sankirtan. But we see that Srila Sukadeva Goswami who narrated Srimad Bhagavatam is the acharya of kirtan. While, Srimad Bhagavatam is hundred percent hari katha and it ends with the sloka:

nāma-saṅkīrtanaṁ yasya
sarva-pāpa praṇāśanam
praṇāmo duḥkha-śamanas
taṁ namāmi hariṁ param  .

.. (S.B 12.13.23)

“Congregational chanting of the Lord’s name destroys all sins. Offering pranam to Him relieves all material sufferings. I offer my pranams to Lord Hari.”

As we see that Srila Sukadeva Goswami is the acharya of kirtan as he narrated Bhagavatam, thus we see that hari katha is also part of kirtan and hari nama sankirtan is just a very specialized form of it that Lord Caitanya Mahaprabhu came to give to the world to deliver.

In fact Srila Gurudev emphasises Hari Katha over chanting. He says that when a hari katha is going on, one should stop the chanting but listen to the harikatha and can resume the chanting after the harikatha.

Thus, nama sankirtan and hari katha are in the same category of kirtan.

Thank you!
Hare Krishna!