Diwali is an auspicious period to perform any Puja. In the Puranas and Holy Scriptures, many pujas are mentioned to observe on Deepavali festival. In 2011, Diwali Amavasya begins in the early morning at 5.16 am on 26 October and continues till midnight 1.26 hrs on 26 October 2011. After this mentioned time, Kartik Sud Pratipada starts. The night of Diwali is the most auspicious muhurat or time to perform Pujas. Devotees prefer Amavasya period for pujas.
26 October 2011 is a rare combination of Swati Nakshatra yogam and Amavasya, hence it is considered highly significant for Lakshmi Puja. (Swati Nakshatra begins after 9.40 pm on 26 October 2011)..
On Diwali festival day, the time between Pradosh kaal and midnight (Nishit Kaal and Mahanishith kaal) is most preferred muhurat for puja. Mahalakshmi Puja, Matruka Puja, Navagraha puja, Lakshmi sahitha Vishnu Pooja, Kubera Puja, Chaturmukha Deepa Prajwalana, etc are performed during this period.
In some places devotees also observe Jagran (vigil). Sri Vishnu Sahasranama stotram, Sri Lakshmi Suktam, Shri Suktam, Purusha Suktam, and Sri Rama Raksha stotram are chanted during the vigil.
Vrushabha lagna and Simha lagna are the only two lagans that are known as Sthira Lagna on Diwali. The time period of these two lagans is most revered time for Deepavali Lakshmi Puja. Deepa Daan puja, Ganesha Puja, Lakshmi Pujan, Chopda Pujan, Sharda Pujan, Maha Kali Pujan, Lekhini Puja, Kubera Puja, etc. are also performed during this muhurat.
Please note: considering all these aspects, Diwali Lakshmi Puja time or muhurat is calculated.