The Reserve Bank of India divides bank holidays into three categories-the Negotiable Instruments Act, the Negotiable Instruments Act, and real-time total settlement holidays and bank closing accounts.
Except for the second and fourth Saturdays and Sundays in October, public and private banks will be closed for several days due to holidays. According to the guidelines of the Reserve Bank of India (RBI), the bank remains closed on all public holidays, but some holidays are regional, that is, restricted to certain states. Regional holidays are determined by the state governments.
The Reserve Bank of India divides bank holidays into three categories-the Negotiable Instruments Act, the Negotiable Instruments Act, and real-time total settlement holidays and bank closing accounts.

The following are the bank holidays in October 2021:

1. October 1-Close bank account half a year (Gangtok)
2. October 2-Gandhi Jayanti (all states)
3. October 3-Sunday
4. October 6th-Mahalaya Amavasye (Agartala, Bangalore, Kolkata)
5. October 7th-Mera Chaoren Houba (Imphal) of Lainingthou Sanamahi
6. October 9th-second Saturday
7. October 10-Sunday
8. October 12-Durga Puja (Maha Saptami) / (Agartala, Kolkata)
9. October 13th-Durga Puja (Maha Ashtami)/(Agartala, Bhubaneswar, Gangtok, Guwahati, Imphal, Kolkata, Patna, Ranchi)
10. October 14-Durga Puja/Dussehra (Maha Navami)/Ayutha Pooja (Agatara, Bangalore, Chennai, Gangtok, Guwahati, Kanpur, Kochi, Kolkata, Lucknow, Patna , Ranchi, Shillong, Srinagar, Thiruvananthapuram)
11. October 15th-Durga Puja/Dasara/Dusshera (Vijaya Dashmi) will be held. All banks will be closed on the day except the banks in Imphal and Shimla.
12. October 16-Durga Puja (Dasain) / (Gangtok)
13. October 17-Sunday
14. October 18-Kati Bihu (Guwahati)
15. October 19-Id-E-Milad/Eid-e-Miladunnabi/Milad-i-Sherif (The Prophet Muhammad’s Birthday)/Baravafat/ (Ahmedabad, Beirapur, Bhopal, Chennai , Dehradun, Hyderabad, Imphal, Jammu, Kanpur, Kochi), Lucknow, Mumbai, Nagpur, New Delhi, Raipur, Ranchi, Srinagar, Trivandrum )
16. October 20th-Maharishi Valmiki’s birthday/Lakshmi Puja/Id-E-Milad (Agartala, Bangalore, Chandigarh, Kolkata, Shimla)
17. October 22-Friday after Eid-i-Milad-ul-Nabi (Jammu, Srinagar)
18. October 23-Fourth Saturday
19. October 24-Sunday
20. October 26-Accession Day (Jammu, Srinagar)
21. October 31-Sunday