Norwich City had a fourth bid for the striker turned down yesterday morning, and there were reports of a fifth bid worth in the region of £9.2m late last night before City were forced to concede defeat in their pursuit.
"Not expecting to do any further business today," tweeted the Norwich chief executive David McNally around 10pm.
Retaining Hooper, who has scored 23 goals this season, will be viewed as a major coup by Celtic and a sign of their intent ahead of the forthcoming Champions League last-16 knock-out tie against Juventus.
The Englishman has 18 months left on his existing contract and has been stalling over an extension, manager Neil Lennon previously stating that the terms of that improved deal would expire come the end of the window.
Celtic had been linked with a move for Johnny Russell if Hooper had been sold. Instead, Sheffield United tested Dundee United's resolve with a bid thought to be in the region of £400,000 that fell short of the Tannadice club's valuation.
Aberdeen were one of the busiest of the rest, making Mark Reynolds' move permanent after the defender was released by Sheffield Wednesday, and signing goalkeeper Dan Twardzik.
Reynolds, who had been on loan at Pittodrie, has signed a four-and-a-half deal after leaving the npower Championship club by mutual consent.
"After a spell of uncertainty, it's great to know I'm going to be in the north-east for the foreseeable future," Reynolds said. "My family settled in Aberdeen very quickly and we really like the area. It's up to me to repay the club's faith in me."
Twardzik, brother of twins Patrik and Filip at Celtic, was last in Italy with Serie C side Como. "After spending a week here earlier in the season, I made up my mind that this was the place I wanted to come to," he said.
St Mirren enticed defender Paul Dummett back from Newcastle United for a second loan spell, having been with Danny Lennon's side in the first half of the season. The Paisley club denied reports midfielder Kenny McLean had been the subject of a bid from an unnamed club in the Championship.
St Johnstone were also busy. Mehdi Abeid joined on loan from Newcastle and could play against team-mates Dummett and Conor Newton, on loan at St Mirren from St James Park, when the teams meet tomorrow in the William Hill Scottish Cup.
The Perth side also took Gwion Edwards on loan from Swansea City until the summer, while Kevin Moon left by mutual consent. They are also expected to take a look at Marcus Maddison next week after the midfielder was released by Newcastle.
St Johnstone held on to Liam Craig, rejecting Hibernian's offer to take the midfielder – who will move to Easter Road under freedom of contract in the summer – four months early. Hibs signed Barnsley winger Matt Done on loan till the end of the season.
Ross County signed defender Branislav Micic from Swiss side FC Sion, and released defenders Ross Tokely and Mark Fitzpatrick.
Motherwell allowed young striker Craig Moore to join Dumbarton on loan, while Dundee took midfielder David Morgan on loan from Nottingham Forest and allowed defender Neil McGregor to join Ayr United on loan for the rest of the season. Kilmarnock have released 20-year-old right-back Alex Pursehouse.
Celtic manager Neil Lennon said he was delighted with the transfer window outcome.
Lennon, who is hoping to complete the loan signing of Swedish keeper Viktor Noring from Trelleborgs and revealed he has had former Manchester United youngster Kenji Gorre, son of SFA youth coach Dean Gorre, on trial at Lennoxtown for a week, said: "I am delighted that we have kept all our main players.
"We have added Tom Rogic, Rami Gershon and hopefully Viktor - we are just waiting on the paperwork coming through - so it has been a decent window for us.
"There was another bid in yesterday (for Hooper), again, an improved offer.
"I am not going to go into the figures but it was substantial.
"We made our position clear and we stuck to that.
"I knew what has happening so it wasn't nervy for me.
"It might have been for supporters but there was a lot of rubbish and speculation being bandied about, a lot of nonsense, but I suppose that comes with the fun of it all."
Meanwhile, keeper Fraser Forster will return for the William Hill Scottish Cup tie against Raith Rovers at Stark's Park on Sunday after recovering from a neck injury and winger James Forrest is back from a hamstring injury.
Lennon is hoping that Georgios Samaras and Emilio Izaguirre, who picked up hamstring and knee injuries respectively against Kilmarnock in midweek, will be back for the Champions League last-16 clash with Juventus at Parkhead on February 12.
He said: "They had scans yesterday so we are hoping that they will both be fit for Juventus.
"It is a small tear for Georgios but we are going to be aggressive with his rehabilitation and our medical people, I wouldn't say they were confident, but they think he has a chance of making Juventus and we are hoping Emilio should be okay."
On Gorre, the Hoops boss said: "He has been released by Manchester United so we have had him in for a week to have a look at him.
"He has done okay, he is a winger, 18, and he is a development-type player."