"Marouane Fellaini has moved to Manchester United for a 27.5 million fee,'' Everton said in a statement.
"Fellaini's exit ended a summer-long period of speculation after the Belgium international emerged as one of former Everton manager David Moyes' prime targets for his new club.''
The move reunites Fellaini with new United manager Moyes, who brought the Belgian to England from Standard Liege in 2008 during his time as Everton coach.
Fellaini becomes United's second close-season signing, after Uruguayan full-back Guillermo Varela joined from Penarol in June.
United were also reported to have submitted an offer to sign Portuguese left-back Fabio Coentrao from Real Madrid on a season-long loan.
However, a mooted move for Athletic Bilbao midfielder Ander Herrera was reported to have collapsed.
Arsenal benefited from the ripple effect of Madrid spending 100 million euros to sign Gareth Bale from Tottenham.
Ozil's signing easily outstrips Arsenal's previous largest transfer - 15 million pounds (then $US21.3 million) for Andrey Arshavin in 2009 - and the club hopes he will help to produce its first trophy since 2005.
Fans had watched in frustration throughout the summer as north London rival Tottenham spent more than $US150 million on seven players, while Arsenal's only permanent recruits were the free signings of Yaya Sanogo and Mathieu Flamini.
But after missing out on Gonzalo Higuain, Luis Suarez and Yohan Cabaye, the Gunners have pulled off the big-name signing promised in June when they said there would be an "escalation in our financial firepower."
"Mr. Kroenke ... has always fully supported Arsene and the club in making significant investments to strengthen our squad and to bring in talented players who fit our style and ambitions," chief executive Ivan Gazidis said.
Ozil's signing pushed spending by Premier League clubs in the summer transfer window over 550 million pounds ($US850 million).
Liverpool, the early unbeaten league leader, was the early mover on deadline-day. Chelsea forward Victor Moses also arrived on loan and young defenders Mamadou Sakho and Tiago Ilori were recruited late to increase their number of summer signings to eight.
Moses will spend the season at Anfield after seeing his chances of first-team action at Chelsea plummet following the arrival of forwards Willian and Andre Schuerrle.
Sakho, who can play at center back or left back and has 14 caps for France, joined from Paris Saint-Germain on a long-term contract and the 20-year-old Ilori, who has represented Portugal at youth age groups, moved from Sporting Lisbon. Financial details weren't disclosed but sections of the British media reported that Sakho and Ilori cost a combined 25 million pounds ($US39 million).
The trio of signings adds strength in depth to a squad that has won its first three league games for the first time since the 1993-94 season to go top of the standings. Sakho and Moses are likely to challenge for first-team places immediately, with the London-born Ilora set to be one for the future.
Liverpool sent striker Fabio Borini on a season-long loan to Sunderland, while another Italian, former Anfield left back Andrea Dossena, joined the northeast club from Napoli.
Stoke signed Austria forward Marko Arnautovic from Werder Bremen on a four-year deal, while Marseille loaned out France midfielder Morgan Amalfitano to West Bromwich Albion.
Manchester United was expected to be busy in the transfer market, but the champions had made no significant signings in the summer window as the deadline loomed.
- AP
