Transport for London (TfL) has confirmed its long-standing ambition to undertake one of the most significant changes to the London Underground network in decades: splitting the busy Northern Line into two separate services. The move, which remains an "aspiration" due to funding constraints, could increase the line's capacity by a substantial 20,000 passengers but may not be realised until the 2040s.
The Proposed Split: How It Would Work
Currently, the Northern Line operates with two central branches through Zone 1, with trains running via either Bank or Charing Cross before merging at Camden Town in the north and Oval in the south. Under the proposed separation, this complex operation would be radically simplified.
The plan would see all services originating from Morden in south London routed exclusively via the Bank branch. Conversely, all trains starting at Kennington or from the Battersea Power Station extension would travel solely via the Charing Cross branch. The northern branches to High Barnet and Edgware would continue to be served by trains from both central branches.
A Long-Held Ambition Stalled by Funding
Plans to separate the line predate 2018 and were first brought to public attention in 2024 via a Freedom of Information (FoI) request. TfL's response at the time outlined the rationale, stating separation would enable a more frequent service but requires more trains.
A key project to procure additional trains was cancelled in 2018 due to funding constraints, dealing a major blow to the proposal. Furthermore, the essential upgrade to Camden Town station – needed to handle the increased passenger interchange from the split – was also deferred. TfL's 2026 position, as reported, confirms the desire remains but the organisation currently lacks the "dosh" to proceed.
The Road Ahead: A Pipe Dream Until the 2040s?
For now, the dramatic reconfiguration of the Northern Line remains a distant prospect. TfL officials have indicated the split is still an "aspiration" but likely will not happen until the 2040s. This timeline aligns with the point at which the Northern Line's existing fleet of trains is due for replacement, potentially offering a logical juncture for such a systemic overhaul.
The separation hinges on two critical factors: securing substantial long-term capital investment and the successful completion of the Camden Town station capacity upgrade. Until these pieces fall into place, the more straightforward journeys promised by the split will remain on the drawing board for London's commuters.
