Portrait of Sir William Chambers is a 1780 portrait painting by the British artist Joshua Reynolds depicting the architect William Chambers.

The Royal Academy had recently moved into new headquarters at Somerset House on the Strand in London.

Reynolds portrays him with a porte crayon in his hand, against the backdrop of Somerset House.

[3] It is likely the painting was produced as a pendant to hang alongside the Self-Portrait by Reynolds in the Assembly Room at Somerset House.

[4] The engraver Valentine Green produced a mezzotint based on the painting, a copy of which is now in the National Portrait Gallery.