The year 1728 in architecture involved some significant events.

• October 20–23 – Copenhagen Fire of 1728.

• Catedral de Nuestra Señora de la Expectación in San Luis Potosí, Mexico, is completed.
• Seaton Delaval Hall in Northumberland, designed by Sir John Vanbrugh (died 1726), is completed.
• White Lodge, Richmond Park, near London, designed by Roger Morris, is completed as Stone Lodge.
• St John's, Smith Square in London, designed by Thomas Archer, is completed for the Commission for Building Fifty New Churches.

• James Gibbs' A Book of Architecture, containing designs of buildings and ornaments is published in London, including a version of the Gibbs surround.

• Grand Prix de Rome, architecture: Antoine-Victor Desmarais.

• February 12 – Étienne-Louis Boullée (died 1799)
• February 25 – John Wood, the Younger (died 1782)^[1]
• July 3 – Robert Adam (died 1792)
• Richard Jupp (died 1799)

• April 10 – Nicodemus Tessin the Younger (born 1654)
• date unknown – Giovanni Barbara, Maltese architect and military engineer (born 1642)