A landmark Grade II listed Edwardian mansion in the heart of Mayfair – once the London home of the Auchincloss family of Jackie Kennedy fame – has been brought to the market, offering a rare opportunity to acquire one of the capital’s most historically significant private residences.
The freehold property at 26 Upper Brook Street, overlooking Hyde Park, extends to almost 13,928 sq ft and includes a central courtyard garden, upper and lower terraces, and a separate mews building to the rear at 4 Wood’s Mews. The estate is being jointly marketed by Wetherell and Knight Frank.
Formerly used as offices, the main townhouse provides substantial accommodation across lower ground, ground and four upper floors.
Westminster City Council has already given positive feedback on reverting the building back to a single-family residence, creating a private home of approximately 11,494 sq ft, with the mews property remaining in commercial use, providing a further 2,434 sq ft of office space.
VALUE UP TO £55 MILLION
A full planning application will still be required for residential conversion, but agents estimate that once restored as a prime Mayfair family home, with offices retained in the mews, the property could achieve a completed value of up to £55 million.
Image Credit: Tony Murray/Casa E Progetti
The proposed residential layout would restore the mansion to its original purpose as a grand private house.
Plans envisage a formal entrance hall with sweeping staircase and passenger lift, a ground-floor family kitchen and breakfast room, and four principal reception rooms.
These would include a formal dining room and family library, along with two interconnecting first-floor reception rooms suitable for entertaining on a large scale.
Image Credit: Tony Murray/Casa E Progetti
The upper floors would provide a full principal suite across the second floor, incorporating bedroom, dressing area, bathroom and study or day room.
The third floor would accommodate two further bedroom suites, each with their own bathrooms, while the top floor would house three additional bedrooms and bathrooms. The lower ground level would offer flexible amenity space, including options for a cinema or club room, staff accommodation, catering kitchen, wine cellar and a large gym with pilates and exercise area.
Image Credit: Tony Murray/Casa E Progetti
To the rear, the mews building would retain two floors of high-specification office accommodation, with a staff flat above comprising living room, bedroom, bathroom and kitchen – creating a rare combination of private residential and professional workspace within a single Mayfair holding.
The dual-building layout also makes the estate suitable for alternative uses, including an ambassadorial residence, embassy complex, or a single or multi-family office headquarters, with formal accommodation in the main mansion and operational offices discreetly positioned to the rear.
AN AMERICAN DYNASTY IN MAYFAIR
The history of 26 Upper Brook Street is as remarkable as its scale. The mansion was built in 1908–09 for James Monro Coats, a wealthy Anglo-American industrialist, by luxury builders Holland & Hannen and designed by renowned architect Arnold Bidlake Mitchell, whose clients included Sir Ernest Cassel, King Leopold of Belgium and Alexander Siemens of the Siemens engineering dynasty.
James Monro Coats was the son of Sir James Coats, a textile magnate and one of the founders of J & P Coats, which later became Coats Viyella.
His mother, Sarah Anne Auchincloss, was the daughter of American banker and industrialist John Auchincloss, linking the family directly to the famous Auchincloss dynasty.
The Auchincloss family connection places the property within the extended family network of Jackie Kennedy, whose stepfather Hugh D. Auchincloss Jr was a close relative.
James Monro Coats himself was born at Hammersmith Farm in Newport, Rhode Island, the Auchincloss estate that later became a childhood holiday home of the future US First Lady.
By the early 20th century, the Auchincloss-Coats family controlled vast commercial interests across textiles, banking and petroleum, with stakes in Standard Oil and leadership roles in Manhattan banking institutions.
Their wealth supported a global portfolio of residences, including Skelmorlie Castle in Scotland, mansions in New York, estates in Virginia and Rhode Island, and the Mayfair mansion at Upper Brook Street.
GILDED AGE ARCHITECTURE IN LONDON
Image Credit: Tony Murray/Casa E Progetti
The original Georgian house on the site was demolished to make way for a new American-inspired mansion – a gilded-age Edwardian trophy house designed to reflect the family’s status and wealth.
The exterior features a Tudor-style Portland stone façade with bay windows and a gable bearing the Auchincloss-Coats family crest.
Internally, the house blends multiple architectural styles.
The entrance hall and principal ground-floor rooms reflect neo-Georgian design, with grand stone fireplaces, decorative cornicing and formal proportions. The first-floor drawing rooms adopt French neo-Rococo styling, with marble fireplaces, Corinthian columns and ornate classical plasterwork.
To the rear of the property, former stable areas were transformed into richly detailed Arts & Crafts rooms, featuring oak panelling, baronial fireplaces, decorative plaster friezes and ornate ceilings, thought to have been designed by George Bankart and executed by craftsmen from the Bromsgrove Guild. These spaces were originally used as James Monro Coats’ private office and cigar lounge, where he entertained business associates and guests.
The house became a focal point of Edwardian social life in Mayfair, hosting figures including Sir Ernest Cassel, Edwina Ashley (later Countess Mountbatten of Burma), and architect Sir Edwin Lutyens.
PRIVATE MANSION TO LANDMARK OFFICE BUILDING
After the deaths of James Monro Coats in 1946 and his wife Anne in 1953, the building was converted into offices.
For many years it served as the London headquarters of the Bank of Africa, the international financial services group headquartered in Casablanca.
Now, for the first time in more than 30 years, the building is returning to the market with the potential to be restored to its original residential purpose.
To support the sale, Wetherell worked with Grosvenor and Knight Frank and commissioned award-winning design house Casa E Progetti to dress and stage the interiors, blending English and French aristocratic styles inspired by the house’s historic heritage.
OUTSTANDING PROVENANCE
Peter Wetherell, Founder and Chairman of Wetherell, says: “The provenance of this Mayfair mansion building offering views onto Hyde Park is outstanding.
“It was originally the London home of a branch of the American Auchincloss family of Jackie Kennedy fame.
“When the Auchincloss-Coats family had the house at 26 Upper Brook Street constructed in 1908–9 they were at the height of their wealth and were the principal shareholders in both J & P Coats and Standard Oil, then two of the world’s three biggest companies.
“The beautiful and ornate interiors of the house reflect that vast wealth and now a discerning buyer has the unique and exciting opportunity to bring this landmark building back to life.”
