The attacking midfielder is reportedly a target for United after impressing at Leicester, where he arrived from Norwich City in 2018.
But in a blow to United, Maddison – who is contracted until 2023 – said he was very happy at the King Power Stadium.
"It's been a whirlwind two years and I've loved every second of it. I feel right at home at Leicester. I feel like part of the furniture already and I love it here," the one-time England international said.
"I love the lads, I love the fans, [we've got] a great manager [Brendan Rodgers], so I'm very, very happy."
Maddison had scored six goals and provided three assists in 28 games to help Leicester sit third when the Premier League season was suspended due to the coronavirus pandemic.
Given a chance to look back, the 23-year-old said he was thrilled with how his move to Leicester had worked out.
"It's been brilliant. It’s gone better than I could ever have imagined to be honest," Maddison said.
"If I think back four years ago, I was on loan at Aberdeen from Norwich and now I'm playing every week in the Premier League and that's all I always wanted to do.
"Sometimes stuff like this can make you really reflect and be proud of myself that I've got to this level and obviously look forward now.
"It's not ideal, but this will give us time to reflect on what's happened, whereas normally you can only think about what's forward because it's the next game… where are the next points coming from?"