The A11 is a major trunk road in England. It originally ran roughly north east from London to Norwich, Norfolk. It now consists of a short section in Inner London and a much longer section in Cambridgeshire, Suffolk and Norfolk. The lengthy section between these was renumbered as a result of the opening of the M11 in the 1970s and then the A12 extension in 1999.

It also multiplexes/overlaps with the A14 on the Newmarket bypass.

All this part has been declassified and is now a minor road. Thus the A11 now starts at Aldgate, just inside the eastern boundary of the City of London. The first stretch is Whitechapel High Street, east of the junction with Mansell Street. In a complex reworking of the roads since the days of the Aldgate gyratory system, it is two-way, but the east-bound section is part of the ring-road that retained a one-way system south of this junction, but the westbound section is for local access and motorists have to U-turn to avoid entering the congestion charging zone.

East of Aldgate station, the A11 enters the London Borough of Tower Hamlets, it becomes Whitechapel High Street (containing Aldgate East Underground station), again part of the Aldgate one-way system. The A11 passes through Whitechapel, past Whitechapel station and the Royal London Hospital.

It becomes Mile End Road at the eastern end of Whitechapel Road, at Mile End Gate, the former toll gate for the turnpike. It passes Stepney Green Underground station, with Stepney to the south, and continues through Mile End, passing the Mile End Underground station. Next, as it continues through Bow, it becomes Bow Road, passing Bow Road Underground station and Bow Church DLR station.

There is a dual carriageway flyover over the Bow Interchange roundabout, a junction with the A12. However at the end of the flyover, as the road crosses into the London Borough of Newham, the A11 designation disappears and it instead becomes the A118. This renumbering followed the opening of the A12 extension in 1999, to make the former A11 seem a less important road and encourage traffic to use the new dual carriageway between there and Leytonstone.

The road number A11 reappears at M11 Junction 9A on the border between Essex and Cambridgeshire, and it is now a trunk road. It roughly follows the route of a Roman road for the remainder of its length.

The A11 formerly went through Newmarket; that stretch is now the A1304. The Newmarket bypass, opened to traffic in July 1975, is a dual carriageway. The western end is the A11, but most of its length is a multiplex/overlap with the A14. The A11 re-appears north-east of Newmarket, and remained a dual carriageway. The road bypasses Barton Mills before entering Norfolk in the Thetford Forest, passing the 113-foot-tall (34 m) Elveden War Memorial. This section of the road opened as a dual carriageway on 12 December 2014. This completes the dualling of the trunk road between Norwich and London.