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18 Grosvenor Square, Mayfair, London, W1K

London

£11,500,000
Listed on 11/05/2026

Property Details

Bedrooms
5
Type
Apartment
Area
4351 sqft

Description

Situated on the sixth and seventh levels of a striking red-brick structure in Grosvenor Square, this expansive five-bedroom penthouse offers an exceptional canvas for renovation. Encompassing approximately 4,351 sq ft, it features a generous south-facing roof terrace of around 722 sq ft, perfect for crafting a stunning outdoor space with views over the square's gardens. The property is being sold via private auction and demands extensive refurbishment throughout. The sixth floor showcases direct lift access leading to a private entrance lobby, from which large reception areas can be found beneath impressive high ceilings adorned with period features. Central to the layout are two spacious reception rooms, complemented by a separate kitchen and dining area. The principal bedroom suite boasts ample space with an ensuite bathroom and dressing room, while three additional bedrooms are also located on this floor, accompanied by a utility room and significant storage solutions. An elegant internal staircase ascends to the seventh floor where an extra reception room grants access to the terrace, providing sweeping views over Mayfair and its gardens. This level further comprises a fifth bedroom suite, study, and powder room, along with a commercial dumbwaiter linked directly to the kitchen below. Belonging to a well-maintained building inclusive of 24-hour porterage services and additional service lift access along with secured storage facilities in the lower ground floor, this apartment lies within the Mayfair Conservation Area but is not listed. This uniqueness allows considerable potential for modification or reconfiguration, pending necessary permissions. Grosvenor Square remains one of London’s preeminent addresses that has seen transformative development recently. With nearby luxury projects such as The Chancery Rosewood and other prestigious developments reinforcing its status in Mayfair’s prime sector, this property is ideally located just 0.3 miles from Hyde Park and approximately 0.2 miles from Bond Street Underground station, ensuring excellent transport connectivity.

Investment Analysis

(W1 area)

Above Market Value

This property is priced +53.9% above area average per sq ft

+53.9%
This Property
£2,643/sq ft
Area Average
£1,717/sq ft
Avg Rent (weekly)
£1,064
Avg Yield
2.8%

Renovation Potential

Heavy Refurb
Est. Renovation Cost
£500,000 - £1,000,000
Target Value
£8,219,409
10% above area average per sq ft
Potential ROI
-34.2%
After renovation
Note: Renovation cost estimates are AI-generated based on property location and general characteristics, and may not reflect actual costs.
Monthly Sales
13
Average per month
Market Turnover
1%
Properties sold annually

Local Market Trend (W1)

Area prices are falling by -14.0% over the last 12 months
3 year growth: -19.2%
5 year growth: -41.0%
Investment Disclaimer: Analysis based on W1 area averages and may not reflect property-specific factors like condition, exact location, or unique features. Any renovation cost estimates provided are AI-generated and should be considered indicative only. Renovation costs vary significantly based on property condition and scope of work. Always conduct professional surveys and get multiple quotes before making investment decisions.

Location

18 Grosvenor Square, Mayfair, London, W1K
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Mortgage Calculator

£
£
£
%
%
years

Current average 2-year fixed rate is 3.97%

Current average variable rate is 6.59%

Monthly Repayments
£41,028
Based on a loan of £8,625,000 over 30 years at 3.97% interest

These results are estimates and are only intended as a guide. Make sure you obtain accurate figures from your lender before committing to any mortgage. Your home may be repossessed if you do not keep up repayments on a mortgage.

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