The Lincolnshire neighbours will meet at The Jakemans Stadium (kick-off 3.00pm) one week before the new Vanarama National League campaign kicks off.
The Mariners are led by former United boss Paul Hurst, while the likes of Shaun Pearson and James McKeown are likely to be in action against their former club.
United have confirmed away trips to Rossington Main, King’s Lynn Town and Worksop Town on Tuesday July 14, Tuesday July 28 and Monday August 3 respectively.
Further home fixtures will be announced in due course.
PRE-SEASON 2015-2016
Tuesday July 14: Rossington Main (A)
Saturday July 25: Lincoln City (H) – LSC
Tuesday July 28: King’s Lynn Town (A)
Saturday August 1: Grimsby Town (H)
Monday August 3: Worksop Town (A)