Downing Street

• Type: Official Residence and Office
• Location: London, England
• Owner/Residents: The Muggle Prime Minister
• Key Features: Contains a magical portrait that facilitates communication between the Minister for Magic and the Muggle Prime Minister.

Downing Street is the real-world residence and office of the Prime Minister of the United Kingdom. Within the wizarding world, it serves as the official point of contact between the Ministry of Magic and the Muggle government. The key to this communication is a special portrait hanging in the Prime Minister's office. The office itself is described as a fine, long room with a marble mantelpiece and sash windows overlooking a lawn. The magical portrait, depicting a “frog-like little man in a long silver wig,” is hung on the wall opposite the windows. According to Cornelius Fudge, this portrait cannot be removed from the wall. Its purpose is to announce the impending arrival of the Minister for Magic, allowing the wizard to travel directly into the office, typically via the Floo Network through the fireplace. The subject of the portrait will cough to get the Prime Minister's attention before speaking. The tradition of the outgoing Minister for Magic introducing themselves to the newly-elected Muggle Prime Minister has been in place for centuries. The purpose of this initial meeting is to inform the head of the Muggle government that a parallel, magical world exists. Subsequent contact is usually reserved for moments when events in the wizarding world are likely to have significant consequences for Muggles.

Downing Street is the setting for the opening chapter of Harry Potter and the Half-Blood Prince, titled “The Other Minister.” The chapter details a visit from the outgoing Minister for Magic, Cornelius Fudge, and his successor, Rufus Scrimgeour, to the incumbent Muggle Prime Minister. During this meeting, the Prime Minister is officially informed of Lord Voldemort's return and the start of the Second Wizarding War. Fudge and Scrimgeour explain that recent catastrophes in the Muggle world, such as the collapse of the Brockdale Bridge and a destructive “hurricane,” were the work of Voldemort and his Death Eaters. They also report the murders of prominent individuals like Amelia Bones and Emmeline Vance. To ensure the Prime Minister's safety during the war, Scrimgeour informs him that Kingsley Shacklebolt, a highly skilled Auror, has been assigned to his office, posing as a new secretary. This chapter firmly establishes the high stakes of the war and illustrates how the wizarding conflict directly impacts the non-magical world at the highest level of government.

• Office of the Muggle Prime Minister: The main setting for all interactions described in the series. It is a long room featuring a desk, a fireplace connected to the Floo Network, and the magical portrait used for communication with the Ministry of Magic.

• Downing Street is a real street in London, England, famous for housing the official residences and offices of the Prime Minister of the United Kingdom and the Chancellor of the Exchequer.
• J.K. Rowling stated that she always imagined a connection between the two worlds at the governmental level and that the Muggle Prime Minister has to be aware of certain events (J.K. Rowling interview).
• The chapter “The Other Minister,” which takes place in Downing Street, was omitted from the film adaptation of Harry Potter and the Half-Blood Prince. The film instead opens with Death Eaters attacking London, including the Millennium Bridge (film).