The US cable operator, which also owns NBC Universal, has received a relatively low level of support. Its confirmed it had received acceptances for 3.84 million of its shares – just 0.21% of its share capital – by the deadline of midday on Wednesday.
Comcast has competition from Fox, which has a deadline of 12.00 GMT on Wednesday 17 for the acceptance of its £24.5 million offer.
In a statement issued Thursday, Sky said it noted Comcast’s extension to its offer timetable.
Fox has been bidding to takeover Sky since December 2017. It faced a number of regulatory hurdles before Comcast entered the bidding the following July.