Soane's three courtyards were also restored with his pasticcio (a column of architectural fragments) being reinstated in the monument court at the heart of the museum.

Soane's collection of paintings includes works by Canaletto, Hogarth, three works by his friend J. M. W. Turner, Thomas Lawrence, Antoine Watteau, Joshua Reynolds, Augustus Wall Callcott, Henry Fuseli, William Hamilton and 15 drawings by Giovanni Battista Piranesi, many of which are framed and displayed in the museum.

There are over 30,000 architectural drawings in the collection, along with various Egyptian, Greek and Roman antiquities, including the Sarcophagus of Seti I. Owing to the narrow passages in the house, all decked with Soane's extensive collections, only 90 visitors are allowed in the museum at any given time, and a formation of queue outside for entry is not unusual.

In 1808–09, Soane constructed his drawing office and "museum" on the site of the former stable block at the back, using primarily top lighting.

The front main part of this third house was treated as a separate dwelling and let as an investment; it was not internally connected to the other buildings.

He also wrote an "anonymous, defamatory piece for the Sunday papers about Sir John, calling him a cheat, a charlatan and a copyist".

[5] Since under contemporary inheritance law George would have been able to lay claim to Sir John's property on his death, Sir John engaged in a lengthy parliamentary campaign to disinherit his son via a private act, setting out to "reverse the fundamental laws of hereditary succession"[6] according to some.

12 has been run by the trustees as part of the museum, housing the research library (until 2009), offices and, since 1995, the Eva Jiřičná-designed 'Soane Gallery' for temporary exhibitions (until Summer 2011).

Since that date the museum has received an annual Grant-in-Aid from the British Government (this now comes via the Department for Digital, Culture, Media, and Sport).

[9][13] Lost rooms recreated include Soane's own bedroom and bathroom, which he showed to the public in his lifetime.

The Library-Dining Room reflects the influence of Etruscan tombs and perhaps even gothic design in its repertoire of small pendants like those in fan vaulting.

As his practice prospered, Soane was able to collect objects worthy of the British Museum, including the Sarcophagus of Seti I, covered in Egyptian hieroglyphs, discovered by Giovanni Battista Belzoni, bought on 12 May 1824 for £2000 (equivalent to £222,000 in 2023)—Soane's most expensive art work.

Turner, Sir Thomas Lawrence, Charles Long, 1st Baron Farnborough, Benjamin Haydon as well as many foreign dignitaries.

[20] Medieval objects include: architectural fragments, mainly from the Old Palace of Westminster (acquired after the 1834 fire), tiles and stained glass.

[21] Soane also purchased four ivory chairs and a table, believed to be made in Murshidabad for Tipu Sultan's palace at Srirangapatna.

[22] Francis Leggatt Chantrey carved a white marble bust of Soane that is still in the museum, in the 'Dome' overlooking the Seti sarcophagus.

[23] Soane also acquired Sir Richard Westmacott's plaster model for Nymph unclasping her Zone, displayed at the back of the recess in the Picture Room.

[24] Other acquisitions include: the plaster model of John Flaxman's memorial sculpture of William Pitt the Younger.

[28] Plastercasts of famous antique sculptures include: Aphrodite of Cnidus,[25] Hercules Hesperides[29] & Apollo Belvedere.

[35] Soane acquired three works by his friend J. M. W. Turner: the oil paintings Admiral Van Tromp's Barge entering the Texel and St Hugues Denouncing Vegeance on the Shepherd of Cormayer Val D'Aoust and the watercolour Kirkstall Abbey.

Thomas Lawrence painted a three quarter length portrait of Soane, it is hung over the Dining Room fireplace in the museum.

[24] Soane owned one oil painting by Joshua Reynolds, entitled Love and Beauty, which hangs in the dining room over the sideboard.

[37] Soane commissioned an oil painting from Augustus Wall Callcott c.1830, entitled The Passage Point -Italian Composition.

[38] Other paintings include The Count of Revenna by Henry Fuseli, and The Landing of Richard II at Milford Haven by William Hamilton.

Of Soane's drawings of his own designs (many are by his assistants and pupils, most notably Joseph Gandy), covering his entire career, most are bound in 37 volumes, 97 are framed on the museum walls, and the rest are 601 covering the Bank of England, 6,266 of his other works, and 1,080 prepared for the Royal Academy lectures.

[41] In 1817 George Dance the Younger gave Soane a gift of a book containing architectural drawings by Christopher Wren, including Hampton Court Palace & Royal Naval Hospital.

The 'Opening up the Soane' project also includes a programme of audience development, a new website and on-line catalogues of the collections.