After a slow start from both teams, Coventry took the lead after 37 minutes when skipper Jim O’Brien steered home from inside the box after a smart cut-back from full-back Chris Stokes.
City had been restricted to speculative long shots before breaking the deadlock – Adam Barton and Matthew Pennington both trying their luck from range without troubling Colchester goalkeeper Sam Walker.
A tame effort from Gavin Massey inside the Coventry box was as close as it came for United in the first half as the visitors struggled to threaten Lee Burge’s goal.
Colchester began the second half much brighter, with George Moncur and Massey both forcing Burge to turn shots away.
The Sky Blues should have doubled their lead when Nick Proschwitz rounded the goalkeeper, but the striker could only find the outside of the post.
Coventry substitute James Maddison’s rasping left-footed shot hit the angle of post and crossbar late on, but the near miss did not prove costly as the hosts claimed all three points.