Anniversaries in January
- 1 January
- 1852 – South Eastern Railway closes its terminus at Bricklayers Arms to passengers.
- 1853 – East & West India Docks & Birmingham Junction Railway renamed as the North London Railway.
- 1866 – London, Chatham and Dover Railway opens Snow Hill tunnel to connect its Ludgate Hill terminus to the Metropolitan Railway at Farringdon.
- 1869 – London and South Western Railway opens lines from Addison Road to Richmond and from New Malden to Kingston.
- 1869 – London, Chatham and Dover Railway connects Herne Hill to Tulse Hill.
- 1878 – Great Eastern Railway opens the Palace Gates Line from Seven Sisters to Wood Green.
- 1897 – Metropolitan Railway connects to Brill Tramway at Quainton Road.
- 1899 – South Eastern Railway and London, Chatham and Dover Railway merge to form the South Eastern and Chatham Railway.
- 1913 – Central London Railway and City & South London Railway are bought by the UERL.
- 1915 – Ilford rail crash kills 10 when an express train collides with a passenger train at Ilford station.
- 1917 – South Acton to Hammersmith & Chiswick line closes to passengers.
- 1923 – Britain's numerous railway companies merge into the "Big Four" (Great Western Railway, London, Midland and Scottish Railway, London and North Eastern Railway and Southern Railway) to improve efficiency.
- 1946 – British European Airways is established as a subsidiary of British Overseas Airways Corporation.
- 1948 – Road haulage, rail and canal companies are nationalised and come under the control of the British Transport Commission. London Passenger Transport Board is replaced by London Transport Executive and railway companies by the Railway Executive.
- 1963 – London Transport Executive is replaced by London Transport Board.
- 1965 – Following the Worboys Committee's review of road transport signage, the first edition of the Traffic Signs Regulations and General Directions is introduced specifying designs and standards for UK signage.
- 1970 – London Transport Board is replaced by Greater London Council's London Transport Executive.
- 1970 – London Transport Country area bus services and Green Line coaches transferred to National Bus Company subsidiary London Country Bus Services.
- 1974 – British European Airways' West London Air Terminal on Cromwell Road closes.
- 2 January
- 1869 – The world's first traffic light installed near the Houses of Parliament and provided with gas-lit lanterns on its semaphore signal arms explodes after less than a month in use injuring the police officer operating it. It is not replaced.
- 3 January
- 1874 – Birth of Sir Charles Bressey, road engineer.
- 4 January
- 2011 – The Western extension of the Congestion Charge Zone is removed.
- 5 January
- 1867 – A signalling error injures 16 when it causes a rear-end collision at Farringdon station.
- 1892 – A train derailment near Farringdon station injures five.
- 1913 – Metropolitan Railway opens "fast lines" from Willesden Green to Neasden.
- 1930 – Southern Railway opens the second section of the Wimbledon to Sutton Line between South Merton and Sutton.
- 1964 – First experiments in automatic ticker barriers start at Stamford Brook.
- 1969 – A crash of an Ariana Afghan Airlines plane on approach to Gatwick Airport kills 48 passengers and crew and 2 on the ground.
- 6 January
- There are no anniversaries today
- 7 January
- 1928 – The River Thames floods from Hammersmith to the City of London breaching the Thames Embankment, causing part of the Chelsea Embankment to collapse and flooding the London Underground, and the Blackwall and Rotherhithe tunnels.
- 1963 – British Railways closes the Palace Gates Line to passengers.
- 8 January
- 1991 – Cannon Street station rail crash kills 2 when a train hits the buffers due to driver error.
- 1999 – Spa Road Junction rail crash injures 4 when two trains collide and derail due to driver error.
- 9 January
- 1933 – Piccadilly line extends from Acton Town to Northfields.
- 10 January
- 1863 – Metropolitan Railway opens between Bishops Road and Farringdon.
- 2009 – Docklands Light Railway extends from King George V to Woolwich Arsenal.
- 11 January
- 1864 – Charing Cross station opens as the London terminus of the South Eastern Railway.
- 1867 – London and South Western Railway absorbs the Thames Valley Railway.
- 1913 – Metropolitan Railway extends "fast lines" from Neasden to Wembley Park.
- 1941 – A German bomb kills 111 when it falls on the Central line ticket hall at Bank station.
- 12 January
- There are no anniversaries today
- 13 January
- There are no anniversaries today
- 14 January
- 1931 – Kingsway tramway subway reopens after reconstruction for use with double-decker trams.
- 15 January
- There are no anniversaries today
- 16 January
- 1941 – A German bomb damages the tunnels at Lambeth North station and injures 20.
- 1944 – Ilford rail crash kills 9 when an express train collides with a passenger train at Ilford station.
- 2013 – A crash of a helicopter into a construction crane at Vauxhall in fog kills the pilot and 1 person on the ground.
- 17 January
- 2008 – A British Airways passenger plane crash lands short of the runway on final approach to Heathrow Airport due to fuel starvation caused by ice in the fuel lines. All passengers and crew survive.
- 18 January
- 1979 – The IRA explodes a bomb close to the Blackwall Tunnel causing fires in nearby gas holders.
- 19 January
- There are no anniversaries today
- 20 January
- There are no anniversaries today
- 21 January
- 1964 – Strand Underpass opens between Waterloo Bridge and Kingsway partly reusing a section of the former Kingsway tramway subway.
- 22 January
- There are no anniversaries today
- 23 January
- 1909 – in what became known as the Tottenham Outrage, two armed robbers fleeing police in Tottenham attempted to escape on a tram.
- 1948 – A collision at London Bridge station kills three when a train overruns a signal and crashes into a train waiting at a platform.
- 24 January
- There are no anniversaries today
- 25 January
- 2003 – A Central line train derails at Chancery Lane when an under-floor motor falls off the train. All Central line and Waterloo & City line services will be suspended for three months whilst modifications are made to 1992 stock trains.
- 26 January
- 1904 – Following his conviction for fraud, James Whitaker Wright, director of the Baker Street and Waterloo Railway, commits suicide at the Royal Courts of Justice.
- 27 January
- 2002 – London Area Control Centre at Swanwick opens to handle air traffic control for London.
- 28 January
- There are no anniversaries today
- 29 January
- 1990 – Holborn Viaduct station closes.
- 30 January
- 1958 – Dagenham East rail crash kills 10 when two trains collide in fog.
- 31 January
- 1915 – Baker Street & Waterloo Railway extends from Paddington to Kilburn Park.
- 1929 – The Fairey Aviation Company begins buying land at Heathrow to build the Great West Aerodrome for test flights of its planes.
