King, in a statement Monday, said his "prime reason" for retiring "was that after 28 years of spending four days a week in Washington, D.C., it is time to end the weekly commute and be home in Seaford."
"This was not an easy decision. But there is a season for everything and Rosemary and I decided that, especially since we are both in good health, it is time to have the flexibility to spend more time with our children and grandchildren," he said. "My daughter’s recent move to North Carolina certainly accelerated my thinking."
The 75-year-old congressman said his decades in Congress have been "an extraordinary experience." He currently serves as a member of the Homeland Security Committee, which he served as chair from 2005-2006 and again from 2011-2012, is a ranking member of the sub-committee on Emergency Preparedness, and also serves on the Financial Services Committee.
"Politically I will miss the energy and dynamism of a reelection campaign especially since my polling numbers are as strong as they have ever been and I have more than $1 million in campaign funds," King wrote in his statement. He said he will continue to be "active politically."
Fox News' Chad Pergram contributed to this report.