| Flat 1, 15 Portman Square, London | Leasehold | 21 m² | £25,000 (2025) |
| Flat 2, 15, Portman Square, London | Leasehold | 24 m² | £180,000 (2006) |
| Flat 3, 15 Portman Square, London | Leasehold | 24 m² | £450,000 (2023) |
| Flat 4, 15 Portman Square, London | - | 37 m² | - |
| Flat 5, 15 Portman Square, London | - | 72 m² | - |
| Flat 8, 15, Portman Square, London | - | 53 m² | - |
| Flat 11, 15 Portman Square, London | Leasehold | 67 m² | £695,000 (2009) |
| Flat 14, 15, Portman Square, London | Leasehold | 71 m² | £400,000 (2006) |
| Flat 15, 15 Portman Square, London | Leasehold | 55 m² | £3,500,000 (2021) |
| Flat 16, 15 Portman Square, London | Leasehold | 144 m² | £2,715,000 (2023) |
| Flat 17, 15, Portman Square, London | Leasehold | 103 m² | £320,000 (2002) |
| Flat 18, 15, Portman Square, London | - | 97 m² | - |
| Flat 19, 15, Portman Square, London | Leasehold | 133 m² | £3,150,000 (2020) |
| Flat 20, 15, Portman Square, London | Leasehold | 91 m² | £555,000 (2004) |
| Flat 23, 15 Portman Square, London | Leasehold | 107 m² | £1,220,000 (2011) |
| Flat 26, 15, Portman Square, London | Leasehold | 84 m² | £1,950,000 (2023) |
| Flat 29, 15, Portman Square, London | Leasehold | 106 m² | £2,150,000 (2022) |
| Flat 30, 15 Portman Square, London | Leasehold | 105 m² | £2,545,000 (2023) |
| Flat 31, 15 Portman Square, London | Leasehold | 142 m² | £1,900,000 (2013) |
| Flat 32, 15 Portman Square, London | Leasehold | 82 m² | £500,000 (2002) |
| Flat 35, 15, Portman Square, London | Leasehold | 107 m² | £2,252,056 (2018) |
| Flat 37, 15, Portman Square, London | Leasehold | 144 m² | £2,000,000 (2022) |
| Flat 38, 15 Portman Square, London | Leasehold | 80 m² | £1,000,000 (2010) |
| Flat 39, 15 Portman Square, London | - | 210 m² | - |
| Flat 41, 15 Portman Square, London | Leasehold | 102 m² | £975,000 (2023) |
| Flat 43-44, 15 Portman Square, London | - | 232 m² | - |
| Flat 44, 15, Portman Square, London | - | 76 m² | - |
| Flat 47, 15, Portman Square, London | Leasehold | 105 m² | £2,100,000 (2017) |
| Flat 49, 15, Portman Square, London | Leasehold | 139 m² | £2,100,000 (2016) |
| Flat 50, 15 Portman Square, London | - | 81 m² | - |
| Flat 51, 15, Portman Square, London | Leasehold | 211 m² | £5,250,000 (2013) |
| Flat 54, 15 Portman Square, London | Leasehold | 105 m² | £2,100,000 (2025) |
| Flat 55, 15, Portman Square, London | - | 150 m² | - |
| Flat 56, 15, Portman Square, London | Leasehold | 80 m² | £1,385,000 (2017) |
| Flat 60, 15, Portman Square, London | Leasehold | 106 m² | £580,000 (2005) |
| Flat 61, 15, Portman Square, London | Leasehold | 105 m² | £535,000 (2003) |
| Flat 65, 15, Portman Square, London | Leasehold | 103 m² | £380,000 (1998) |
| Flat 66, 15, Portman Square, London | Leasehold | 107 m² | £2,700,000 (2025) |
| Penthouse A, 15, Portman Square, London | - | 244 m² | - |
| Penthouse B, 15 Portman Square, London | - | 231 m² | - |
| Penthouse D, 15 Portman Square, London, London | - | 150 m² | - |
| Penthouse E, 15 Portman Square, London | Leasehold | 194 m² | £1,150,000 (2006) |
| Suite B, 15 Portman Square, London | - | 129 m² | - |
