The Sikh Calendar
The Nanakshahi (Punjabi: ਨਾਨਕਸ਼ਾਹੀ, nānakashāhī) calendar is a tropical solar calendar that was adopted by the Shiromani Gurdwara Prabhandak Committee to determine the dates for important Sikh events. It was designed by Pal Singh Purewal to replace the Saka calendar and has been in use since 1998. The epoch of this calendar is the birth of the first Sikh Guru, Nanak Dev Ji in 1469. New Year’s Day falls annually on what is March 14 in the Gregorian Western calendar.
Calendars are important because they help us organize celebrations across the Sikh diaspora. Many of the Sikh holidays occur on the same date each year, while some move around, namely Hola Mohalla, Bandi Chhor Divas, and Parkash Guru Nanak Sahib.
Sikh
Month Begins
Chet March 14
Vaisakh April 14
Jeth May 15
Harh June 15
Sawan July 16
Bhadon August 16
Asu September 15
Katik October 15
Maghar November 14
Poh December 14
Magh January 13
Phagan February 12
For more info
Sikhnet
Sikhiwiki
BBC Calendar