Season ender 'Valar Morghulis' will run for 64 minutes, according to HBOWatch.
Most Game of Thrones episodes run to around 54 to 55 minutes in length, meaning that the finale will include 10 minutes of additional material.
The episode - written by David Benioff and DB Weiss - will air on June 3 in the US and will be broadcast the following day on Sky Atlantic in the UK.
It was recently reported that each episode of the fantasy drama, which shoots on location in countries like Croatia, Iceland and Northern Ireland, costs around $6 million to produce.
A third season of Game of Thrones will debut in early 2013.
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Watch the stars of Game of Thrones discuss season two with Digital Spy below: