A product of the Huddersfield Town academy, the 27-year-old has played most of his football in spells at AFC Telford United and Harrogate Town.
Killock joins the club from Evo-Stik Northern Premier League First Division North side Scarborough Athletic, who he joined in January following a short spell at Hyde United.
Having spent his younger days at Huddersfield, Killock moved to Ossett Albion and featured in the Northern Premier League at just 15 years old.
He then returned to Town, making one league appearance and spending time on loan with Hyde, Harrogate and Oxford United, for whom he signed permanently in 2009.
However, his time at Oxford was short-lived, and a loan move to Telford was soon turned permanent.
He spent over three seasons playing at the New Bucks Head, making 132 appearances and scoring four goals.
In 2012, he returned to Yorkshire and joined Harrogate Town, where he spent three seasons and made twenty-nine league appearances, and also had a loan spell at Guiseley.
Last term his season was badly affected by a horrific injury suffered incidentally at Ossett Albion, fracturing a number of bones in his face.
“I’m really looking forward to it,” Killock said. “Alex Meechan rang me, and from there I couldn’t wait to get going.
“It’s a good club and it’s a good level to be playing at. It will be a tough league next season but I can’t wait for it to start.
“I always work my hardest, as a centre half obviously I love to get stuck in.
“I give 110%, always wear my heart on my sleeve and put a shift in for the team, wherever I’m asked to play doing whatever I’m told to do”.