October 2012 is one of the biggest months for Hindus in which the biggest festivals for Hindus, Pitru Paksha, Navratri Durga Puja, Vijayadashami and Kojagari Purnima Lakshmi Puja are celebrated along with the holy Ashwin Month & Kartik month.
Here is the list of important Hindu festivals in October 2012:
1 October 2012: Dwitiya Shraddh. Ashwin Month begins in North India. Panchak ends. Ashunya Shayan Vrat.
2 October 2012: Tritiya Shraddh. Undralla Thadde in Andhra Pradesh. (Bruhath Gauri Puja).
3 October 2012: Sankatahara Chaturthi, Maha Bharani. Bharani Mahalaya Shraddh.
4 October 2012: Krithikai Vratha. Chaturthi Shraddh.
5 October 2012: Panchami Shraddh. Sri Chandra Sashti.
6 October 2012: Sashti Shraddha. Sri Dnyaneshwari Jayanti.
7 October 2012: Bhanu Saptami. Saptami Shraddha. Jivitputrika Vrat Nahai Khai.
8 October 2012: Mahaa Vyadeepaadam, Madhyashtami Shraddh. Ashtami Shraddh. Kalashami. 16-day Mahalakshmi vrata ends. Jivitputrika Vrat. Jitiya Puja in Bihar.
9 October 2012: Avidhva Navami. Navami Shraddh. Matru Navami. Sowbhagyavati Shraddha.
10 October 2012: Dashami Shraddha. Surya Ka Chitra Nakshatra Pravesh (Sun God enters into Chitra Nakshatra). Shani Astha. Charakha Jayanti.
11 October 2012: Indira Ekadasi. Ekadasi Shraddha. Magha Shraddh.
12 October 2012: Dwadashi Shraddh. Sanyasi Mahalaya.
13 October 2012: Pradosha Vrata, Monthly Shivaratri. Trayodashi Shraddha.
14 October 2012: Bodhayana Amavasai. Chaturdasi Shraddh. Ghat Chaturdasi. Shastradihath Pitru Shraddha.
15 October 2012: Mahalaya Amavasya. Sarvapitru Darsh Amavasya. Somvati Amavasya. Amavasya Shraddha. Bhavanidevi Nidrakaal ends. Mahalaya Paksha ends.
16 October 2012: Chandra Darshan, Shardiya Navratri begins with Ghatasthapana. Matamaha Shraddha. Mahur Renukadevi Navratri Utsav begins. Sant Muktabhai Jayanti. Ambadevi Utsav. Dhwajarohan. Maharaj Agrasen Jayanti.
17 October 2012: Tula Sankranti. Thula Vishu Punyakalam, Aippasi Masam begins in Tamil calendar. Thulam month begins in Malayalam calendar. Kaveri Sankraman Snan. Saur Kartik Maas begins (Kartik Month begins in Bengal).
18 October 2012: Muhurtha Day, Chaturthi Vratha. Vinayak Chaturthi. Saptaratri Utsav begins. Sindhur Tritiya Vrat.
19 October 2012: Lalitha Panchami. Upang Lalita Vrat. Pancharatri Utsav begins.
20 October 2012: Shashti Vratha. Saraswati Avahan.
21 October 2012: Saraswati Pujan. Mahalakshmi Pujan. Bhanu Saptami. Durga Puja begins in Bengal. Triratrotsav begins. Pushkar Muni Jayanti.
22 October 2012: Durgashtami, Mahashtami Upvaas. Saraswati Balidaan / Visarjan. Ekratrotsav begins. Sri Mahalakshmi Jaagar Kolhapur. Bhadrakali Avataar.
23 October 2012: Shravana Vratha, Mahanavami, Saraswati Pooja, Ayudha Pooja. Ayudh Navami. Mahanavami Upvaas. Surya Ka Swati Nakshatra pravesh. Navratri Udyapan Paaran. Devi Ko Balidaan. Panchak begins. Ekaveera Mahanavami Pooja. Ambadevi Navratri. Ekaveera Devi Navratri. Renukadevi Navratri utsav ends. Shastra Pooja.
24 October 2012: Vijayadashami. Dussehra (Dasara). Vijay Muhurat. Shirdi Saibaba Punyatithi. Sri Madhvacharya Jayanti. Aparajita Pooja. Shami Pujan.
25 October 2012: Ekadasi (Pasankusha Ekadasi). Bharat Milaap. Sri Bhavanidevi Nidrakaal prarambh in Tuljapur. Burhanpur Balaji Mela.
26 October 2012: Ksheerdaan Dwidala Vrata. Padmanabha Dwadashi.
27 October 2012: Shani Pradosha. Vastu Day.
28 October 2012: Muhurtha Day. Panchak ends. Shakambari Devi Darshan Saharanpur.
29 October 2012: Ashwin Paurnami Vratha. Abhishekam. Kojagari Purnima Lakshmi Pujan. Maharshi Valmiki Jayanti. Karthik Snan arambh in North India. Navanna Purnima. Kumar Purnima. Sharad Purnima. Akash Deepdaan. Tuljapur Bhavani devi Utsav. Bhavani Devi Nidrakaal ends.
30 October 2012: Kartik Month begins in North Indian Hindi calendars. Krushi Bhumipujan. Vishnu Pooja.
31 October 2012: Krithikai Vratha. Ashunya Shayan Vrata. Guru Ramdas Jayanti.
October 2012 coincides with Ashwin month and Kartik month in North Indian Hindi calendars. It coincides with Bhadrapada month and Ashwin month as per Gujarati, Marathi, Telugu, and Kannada calendars. In Bengali calendar, October 2012 coincides with Ashin Mash and Kartik Month. It coincides with Purattasi and Aippasi Masam of Tamil calendar; Kanni Masam and Thulam Masam of Malayalam calendar.