McCartney, 69, and Shevell, 51, first left their home at 7 Cavendish Avenue in St John's Wood at 11.15am in a maroon Lexus car. The car took the couple, who wore dark tracksuits, to nearby Lord's cricket ground, where they went to the gym. They returned to Cavendish Avenue at 12.30pm. Asked by reporters how he was feeling ahead of the wedding, McCartney gave the thumbs up.
A tent was erected in the driveway of the Cavendish Avenue house two days prior to the wedding, and champagne, flowers, party decorations and furniture were brought into the house. Refrigerators in the grounds were filled with non-vintage Dumangin Grande Reserve champagne.
Speculation mounted as the day progressed, and at 3.06pm the couple once again emerged, with McCartney's daughter Beatrice, 7, a flower girl at the wedding. McCartney sat in the front of the Lexus alongside the driver, while Shevell was in the back with Beatrice.
The couple arrived at Old Marylebone Town Hall at 3.20pm. Shevell wore a simple ivory dress, designed by Stella McCartney, and a white flower in her hair. They exchanged rings reportedly from Los Angeles jeweller Neil Lane.
Just 30 guests attended the ceremony, among them Ringo Starr and his wife Barbara Bach. McCartney's son James was his best man.
The ceremony lasted just over an hour. Sir Paul and the new Lady McCartney left the register office at 4.31pm, and arrived back at Cavendish Avenue at 4.38pm. They posed briefly for photographers before going inside the house.
The wedding was conducted by superintendent registrar Alison Cathcart, at a cost of £1,540. The couple filed their notice of intent to marry on 14 September 2011 at Old Marylebone Town Hall.
The best thing about being a registrar is the knowledge that in one moment you have changed people's lives, and I'm delighted that Paul and Nancy have chosen Marylebone Town Hall for their special day.
I am honoured to be conducting the ceremony and will get to see the look of joy on both their faces when I declare them husband and wife.
Following the wedding, a party was held at Cavendish Avenue, where around 100 guests were served salmon and truffle risotto and £110-a-bottle organic champagne. The menu was designed by McCartney's daughter Mary. The chocolate wedding cake took two people to carry in, and took "weeks" to make, according to Posh Puds Patisserie.
Guests at the party included Sir David Frost, Twiggy, Tracey Emin, Sam Taylor-Wood, Aaron Johnson, Barbara Walters, Jools Holland, Jeff Beck, David Gilmour and John Frieda. Mark Ronson was the DJ.
During the reception McCartney also performed a new song written for Nancy. He sang My Valentine with an acoustic guitar accompaniment.
Paul performed a special song late in the evening. He had written it especially for 'his lovely' Nancy for this day.
It was lovely. She was truly touched and looked as though she shed a tear. I had a lovely time. It was superb. It couldn't have been more superb or perfect a wedding.
At around 1.30am two noise control officers from Westminster City Council arrived at the house to ask McCartney to turn down the volume, following complaints from local residents. The officers spoke to a security guard in the front garden.
The last people to leave the party, at 3am, were model Kate Moss and The Rolling Stones guitarist Ronnie Wood.
There was a lovely song that our kid did and they had a lovely dance together, so that was a nice little highlight of the evening.
The marriage is McCartney's third and Shevell's second. His first wife Linda died of breast cancer in 1998; he married Heather Mills in 2002, but they separated in 2006 and divorced two years later.
Shevell was married for over 20 years to US attorney Bruce Blakeman. She serves on the board of New York's Metropolitan Transportation Authority, and is a vice president of a New Jersey-based trucking company owned by her father.
McCartney later released a statement about the wedding on his official website.
Nancy and I want to thank everybody for the wonderful greetings and messages of goodwill that we received. We had a really great day with family and friends; it was relaxed, fun, emotional, heartfelt and a total pleasure for the two of us and everyone involved.
You may have read, in the media, some of the details about our happy day but, as not all of what was reported was totally true, here are a couple of corrections for those of you who like to know the truth:
It was said that my brother, Mike, was my best man. In fact, it was my lovely son, James, who did me proud. It has been said that Stella designed the menu. In actual fact, it was my daughter Mary who did. It was also reported that I sang Let It Be and Let Me Roll It at the reception but, in actual fact, that's not true and I think the reporters may have got confused by hearing a few of my other songs being played by our DJ for the night, Mark Ronson, who, by the way, did a sensational job, keeping us all bopping till the early hours of the morning.
But even though they got one or two things wrong, what they did get right was that Nancy and I, and all our lovely guests, had an unbelievably great day and send our love to all of you.