The Bluebirds spent more than £30million in the summer as they brought in
reinforcements including Steven Caulker and Gary Medel ahead of their first season in the Premier League.
Cardiff's January business is likely to be in the spotlight after the departure of recruitment chief Iain Moody, and the subsequent visa issues of his replacement Alisher Apsalyamov, but Mackay is confident of bolstering defence, midfield and attack.
"It would be great if we can bring in three quality additions to the squad," said Mackay.
"I would look to strengthen all three departments in terms of a defender, a midfielder and an attacking player.
"I will talk to my chairman (about January) who will then discuss it with his board of directors and our owner and I will take my lead from them.
"It's up to them then what financially they want to spend in January. I've got my lists of players, whether they be permanent targets or loans for various positions. We've got to try and strengthen again.
"We are a first-time club so to speak. Everyone barring two other clubs has got a massive head start on us in terms of quality. They might only need to bring in one or two over a season. We had to bring in a group of eight players which was going to give us the chance to survive.
"You have a choice: do you invest knowing you have a really good chance of
staying up or do you invest knowing you might go down and then have to build again?
"There's not quite the array of talent out there in January and people are leaving clubs for different reasons and overall you have to be careful. It's about bringing in another layer of quality to add to what we've got. I need to bring in guys who are going to add to that."