Key points

• New Great Northern and Thameslink timetable takes effect from Sunday, 14 December, following a £4 billion, decade‑long upgrade of the East Coast Main Line.​
• Extra peak‑time services will run between Cambridge, Letchworth Garden City and London King’s Cross to increase capacity and provide more evenly spaced departure times.​
• A new half‑hourly Letchworth Garden City–London King’s Cross stopping service will operate in the peaks, with a second half‑hourly peak service also running between Letchworth Garden City and London King’s Cross.​
• Key intermediate stations to benefit include Hitchin, Stevenage, Knebworth, Welwyn North, Welwyn Garden City, Hatfield, Potters Bar, New Barnet, Alexandra Palace and Finsbury Park, with selected services extended to Royston.​
• Govia Thameslink Railway’s chief operating officer, John Whitehurst, says the timetable will deliver more space at peak times, quicker journeys to and from London and more regular departures for customers travelling between London, Hertford North, Cambridge and King’s Lynn.​
• The timetable is designed to be ready for new services at Cambridge South station when it opens in June, with all Cambridge–London King’s Cross services scheduled to stop there from June 2026.​
• Peak Cambridge–King’s Cross services currently operating half‑hourly will be split into two half‑hourly groups, effectively doubling capacity and including a new semi‑fast service via Foxton, Shepreth, Meldreth, Royston, Ashwell & Morden, Baldock, Letchworth Garden City, Hitchin and Welwyn North.​
• A new 4.54pm service from London King’s Cross to Cambridge is expected early next year; until then, the 4.27pm train to Letchworth will be extended to Cambridge to preserve similar timings north of Letchworth.​
• A new 8.45am Letchworth–King’s Cross service is planned for early next year, with passengers able to complete journeys using existing alternatives in the meantime.​
• There will be no 6.27pm London King’s Cross–Letchworth departure because of pathing conflicts with long‑distance East Coast Main Line services.​
• Weekday peak Great Northern services between Peterborough and London King’s Cross remain at five trains in both morning and evening peaks, with the current 8.05am departure moved significantly earlier to 5.43am.​
• On the Moorgate route, two existing morning services that currently start at Gordon Hill will instead start from Hertford North, boosting capacity at Hertford North, Bayford, Cuffley and Crews Hill.​
• Some Thameslink services between Peterborough, Cambridge and London will see minor timing changes to improve connections, while Thameslink’s Cambridge–Brighton trains will call at Cambridge South once it opens in June 2026.​

Great Northern and Thameslink timetable customers can expect

Rail passengers in north London, Hertfordshire and Cambridgeshire are being promised more peak‑time capacity, faster trips into the capital and more regular departures as a new Great Northern and Thameslink timetable comes into force on Sunday, 14 December, following a decade‑long £4 billion investment in the East Coast Main Line. The updated schedule brings extra trains on key commuter routes into London King’s Cross, prepares the network for the opening of Cambridge South station and makes a series of detailed adjustments affecting customers from Peterborough to Brighton.​

What is changing in the new timetable?

The new timetable, already loaded into online journey planners and detailed at the dedicated website, represents one of the most substantial recasts on the route since the East Coast Main Line upgrade programme began. The changes focus on peak‑time flows into and out of London King’s Cross, where passenger demand is highest and where recent infrastructure work allows operators to make fuller use of available capacity.​

Govia Thameslink Railway, which runs the Great Northern and Thameslink brands, states that the new pattern is designed to match train paths more closely to current and expected demand, while maintaining resilience on a corridor that must balance commuter, regional and long‑distance inter‑city services. Passengers are being urged to check their individual journeys before travelling, as some trains have new departure times, stopping patterns or extended routes even where headline frequencies appear unchanged.​

How will Cambridge and Letchworth services be boosted?

A central element of the timetable change is the enhancement of peak‑time services linking Cambridge, Letchworth Garden City and London King’s Cross. Commuters on this corridor will see additional trains introduced in the busy morning and evening periods, with the aim of reducing crowding and cutting waiting times between departures.​

There will be a half‑hourly Letchworth Garden City to London King’s Cross stopping service during the peaks, supplemented by a second half‑hourly service that also links Letchworth Garden City with King’s Cross in peak hours. Together, these trains will call at Hitchin, Stevenage, Knebworth, Welwyn North, Welwyn Garden City, Hatfield, Potters Bar, Alexandra Palace and Finsbury Park, reinforcing the service for communities across north London and Hertfordshire.​

Which intermediate stations gain extra calls?

As part of the revised pattern, selected trains on the Letchworth–King’s Cross route will additionally call at New Barnet in the morning peak to provide extra capacity for passengers boarding there. In a further connectivity gain, one morning and one evening service will be extended beyond Letchworth Garden City to Royston, improving direct links for that town.​

These changes are intended to share demand more evenly between trains and stations, giving passengers additional options when planning journeys into and out of London. They also align with broader efforts to spread the peak and avoid excessive crowding on individual services where reasonable alternatives exist within a short time window.​

What does Govia Thameslink Railway say about the benefits?

John Whitehurst, chief operating officer of Govia Thameslink Railway, frames the timetable change as a targeted response to customer needs on some of the network’s busiest flows. According to Whitehurst, the re‑worked pattern will bring

“more passenger space at peak times where it is needed most, quicker trips to and from London from key destinations and more evenly spaced departure times so customers don’t need to wait as long for a train”

for those travelling between London, Hertford North, Cambridge and King’s Lynn.​

Whitehurst also emphasises that the new schedule is forward‑looking, explaining that it will

“ensure we are ready for new services to be introduced at Cambridge South station when it opens in June”.

The operator highlights that careful planning has gone into balancing immediate benefits with readiness for upcoming infrastructure changes, particularly around Cambridge.​

How is the timetable preparing for Cambridge South?

Cambridge South station, under construction to serve the biomedical campus and growing employment hub in the south of the city, is due to open in June, with a further step‑change in June 2026. From that later date, all services between Cambridge and London King’s Cross are scheduled to call at Cambridge South, embedding the new stop into the core Great Northern timetable.​

To support this, the existing half‑hourly peak‑time services from Cambridge to London King’s Cross will be replaced by two distinct groups, each running at half‑hourly frequency and thus doubling overall capacity in those periods. The approach is meant to give operators the flexibility to serve both the traditional city centre markets and the expanding Cambridge South catchment without compromising reliability.​

What new semi‑fast services will operate from Cambridge?

Under the new plan, one of the Cambridge–King’s Cross groups will operate as a semi‑fast service, striking a balance between journey time and coverage. This semi‑fast pattern will call at Foxton, Shepreth, Meldreth, Royston, Ashwell & Morden, Baldock, Letchworth Garden City, Hitchin and Welwyn North, offering key intermediate communities faster access to London and to Cambridge.​

The semi‑fast trains are designed to complement stopping services, giving passengers a choice between speed and more local coverage. For many stations, the combination will mean a more frequent overall service as well as a clearer, more predictable pattern of fast and stopping options throughout the peaks.​

When will the new afternoon and morning trains start?

Among the more specific timetable changes is the introduction of a new 4.54pm service from London King’s Cross to Cambridge, which is expected to begin operating early next year. Until that train is launched, the current 4.27pm service from King’s Cross to Letchworth will be extended through to Cambridge, preserving broadly similar timings for travellers heading to stations north of Letchworth.​

In the morning peak, a new 8.45am departure from Letchworth to King’s Cross is also planned for early next year, further boosting choice for commuters and other passengers. Until that service is introduced, customers will be directed to use other existing trains to complete their journeys, with operators stressing that sufficient capacity will remain available.​

Why will there be no 6.27pm Letchworth departure?

One notable omission from an otherwise regular pattern is the absence of a 6.27pm departure from London King’s Cross to Letchworth. While most services are designed to repeat every 30 minutes, this particular time has been ruled out due to conflicts with long‑distance East Coast Main Line operations.​

The decision reflects the tight constraints on the shared infrastructure north of London, where commuter and inter‑city trains must operate within fixed capacity limits. Network planners have concluded that maintaining paths for longer‑distance services at that time is essential, even though it means leaving a small gap in the otherwise even Letchworth pattern.​

What remains the same for Peterborough peak services?

For passengers travelling between Peterborough and London King’s Cross on Great Northern, the headline number of weekday peak services will remain unchanged at five trains in both the morning and evening peaks. This continuity is intended to provide stability on a route that is also served by long‑distance operators, where major alterations could have knock‑on effects across the East Coast Main Line.​

However, there is a significant timing change to one key train: the current 8.05am departure from Peterborough will be moved earlier to 5.43am. This adjustment is likely to affect commuters who have become accustomed to the later departure, and they are being advised to check alternative services and new timings that best fit their working patterns.​

How will the Moorgate route see capacity gains?

On the Moorgate route, which links central London with Hertfordshire via the Northern City Line, the timetable changes aim to relieve pressure at several busy intermediate stations. Two existing morning peak trains that currently originate at Gordon Hill will, under the new schedule, instead start their journeys at Hertford North.​

By beginning further north, these services will create extra capacity from Hertford North, Bayford, Cuffley and Crews Hill, where demand has been growing. The operator anticipates that this will be particularly welcomed by passengers who have previously struggled to board at these stations on busy mornings.​

What minor adjustments affect Thameslink services?

Beyond the flagship Great Northern changes, a series of smaller timing adjustments will be made to Thameslink services operating between Peterborough, Cambridge and London. These tweaks are designed to improve connections, reduce conflicting movements and fine‑tune punctuality across the network.​

The Cambridge–Brighton Thameslink service, a key cross‑London route, is also set for a significant enhancement linked to the opening of Cambridge South. Once the station comes into use in June 2026, these trains will call there, giving passengers a direct link from the new station through central London and on to Gatwick Airport and the south coast.​

How should passengers prepare for the changes?

Passengers are being advised to familiarise themselves with the new timetable well before travelling, particularly if they rely on specific trains for commuting, school or connecting services. Journey planners and the dedicated timetable website have been updated to reflect the revised pattern, allowing customers to compare old and new timings in detail.​

While many of the changes are framed as improvements, some travellers may need to adjust routines, especially those affected by the retimed Peterborough services or the absence of a 6.27pm Letchworth departure. The operator stresses that the overall goal of the recast is to provide more capacity where it is most needed, better prepare for new infrastructure, and deliver a more reliable and evenly spaced service across the East Coast Main Line corridor.