Although Margetson's contract with the Championship club expired on June 30, Swansea were entitled to compensation for the 19-year-old's development after he progressed through their academy from Under-15 level. The two clubs have now agreed on a compensation package, allowing the goalkeeper to complete his move to Old Trafford.
The transfer marks United's fourth signing of the summer as they continue to invest in young talent.
Margetson leaves Swansea without making a senior appearance for the club, but gained valuable first-team experience during a season-long loan at Cymru Premier side Connah's Quay Nomads. He featured 34 times, keeping 10 clean sheets as the club secured qualification for European competition.
The goalkeeper has also represented Wales at youth level and made his Under-21 debut against Belarus in March. He is the son of former Wales international goalkeeper Martyn Margetson, who previously worked as Swansea's head of goalkeeping before leaving the club at the end of the 2025-26 season.
Confirming the move, United said: "Manchester United have agreed the signing of exciting young goalkeeper Kit Margetson, subject to registration.
"The 19-year-old was most recently at Swansea City, a club he'd been with since under-15s. Last season, he had his first taste of senior football on loan at Connah's Quay Nomads and kept 10 clean sheets in 34 appearances, helping the Welsh side to qualify for European competition.
"Margetson has also earned youth international caps for Wales and made his Under-21s debut against Belarus in March. Everyone at United would like to welcome Kit to the club and wish him the very best of luck for the future."
United have not disclosed the length of Margetson's contract, but the highly-rated goalkeeper arrives as another long-term investment for the club's academy and senior setup.
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