Plans for High Speed 2 and Crossrail 2 both include proposals to modify the station to provide interchanges with the new services.

[7][n 1] The company planned a route to run from Heath Street in Hampstead to Strand in Charing Cross with a branch diverging from the main route to run under Drummond Street to serve Euston, St Pancras and King's Cross stations.

[15] At the time, the C&SLR was in the process of constructing an extension to Angel from its recently opened terminus at Moorgate Street.

[16][n 3] The extension plan was initially permitted in 1901, but delays in the parliamentary process meant that it had to be re-submitted the following year.

The second submission was opposed by the Metropolitan Railway, which saw the extension as competition to its service between King's Cross and Moorgate, and the plan was rejected.

[23] A separate bill was published at the same time by the London Electric Railway (LER),[n 5] that included plans to construct tunnels to connect the C&SLR at Euston to the CCE&HR's station at Camden Town.

[26] Together, the works proposed in these bills would enable trains of each company to run over the route of the other, effectively combining the two separate railways.

[31] Between 1946 and 1954, a series of routes were proposed by different transport authorities to connect various places in south and north or north-east London.

To provide cross-platform interchange, a new section of tunnel was constructed for northbound Bank branch trains, which were diverted to a new platform south of the original alignment.

[n 8] The redundant northbound track bed in the station tunnel was filled in to form a wider southbound platform.

[n 9] In conjunction with the reconstruction of the main line station above, a new ticket hall was excavated below the concourse with two sets of escalators replacing the lifts.

The escalators provide access to and from an intermediate passenger circulation level, which, in turn, gives access to the Northern line Charing Cross branch platforms and two further sets of escalators; one set each serving the northbound and southbound Victoria and Northern line Bank branch platforms.

[39] Interchanges between the northbound and southbound Victoria and Northern Bank Line platforms are made via a passageway at the lower level so as to avoid the need to use the escalators.

[42] Plans for the redevelopment of the main line station for High Speed 2 (HS2) include the construction of a direct connection to Euston Square.

On the Northern line's Bank branch the station is between Camden Town and King's Cross St Pancras.