Two things keep a journey with a change of trains on one fare in London. Pink card readers, at 17 interchange stations, tell the system you went round Zone 1 rather than through it, so you pay the lower fare. Out-of-station interchanges, a published list of about 130 station pairs, let you touch out, walk along the street and touch in again within a set number of minutes without starting a new journey.
Both exist because pay as you go only sees where you touched in and where you touched out. Without help, the system cannot tell that you avoided the expensive centre, or that the Tube station you left and the railway station you entered were part of the same trip. The pink reader and the walking allowance fill in those gaps.
The basic rules of pay as you go and the daily caps are on our guide to Oyster and contactless, and the zone map is explained in London's travel zones. This page is only about the change of trains in the middle.
One journey, one fare: the essentials
- Pink card reader
- Touch it when you change trains on a route that avoids Zone 1. It does not start or end a journey
- Pink reader stations
- 17, listed on TfL's pink card reader page
- Out-of-station interchange
- Touch out, walk, touch in at the listed station within the time allowed
- Typical walking allowance
- 10 to 40 minutes, set separately for each pair and each direction
- Works with
- Contactless and Oyster pay as you go; paper tickets at a smaller number of pairs
- Still applies
- The overall maximum journey time for the whole trip
- TfL's list dated
- Data up to 1 March 2026, file updated September 2026
Pink card readers: where they are and what they do
A pink card reader looks like the usual yellow reader but is coloured pink, and it stands on or between the platforms where two lines meet. TfL's instruction is three steps: touch in on a yellow reader at the start, touch the pink reader when you change trains, and touch out on a yellow reader at the end. The pink touch records your route. It costs nothing and it does not interrupt the journey.
TfL lists pink readers at these stations:
- Blackhorse Road, Canada Water, Clapham Junction, Ealing Broadway, Gospel Oak, Gunnersbury
- Hackney Central and Hackney Downs, Highbury & Islington, Kensington (Olympia), Rayners Lane, Richmond
- Stratford, Surrey Quays, West Brompton, Whitechapel, Willesden Junction, Wimbledon
They work with contactless, Oyster and Travelcards on the Overground, the Elizabeth line and the Tube. Most of them are on the Overground's orbital routes, and that explains the list: these are the places where a journey across London can swing round the centre instead of through it. Our page on the Overground's six line names shows which line is which.
You only need one when you actually change trains. Staying on a single train that already avoids Zone 1, such as a Mildmay line train from Hackney Central to Richmond, is charged correctly without any pink touch.
What skipping the pink reader costs
If you change trains at one of these stations and do not touch pink, TfL charges the higher pay as you go fare that includes Zone 1. With a Travelcard that does not cover Zone 1, you are charged an extension fare you did not need to pay. The difference is not small,, as TfL's own single fare finder shows for a journey from Walthamstow in the north-east to Richmond in the south-west.
| Walthamstow Central to Richmond, adult pay as you go | Off-peak | Peak |
|---|---|---|
| Fare the system assumes (via the centre) | £3.60 | £4.80 |
| Avoiding Zone 1, changing at Highbury & Islington or Hackney Downs/Central, with a pink touch | £2.40 | £3.20 |
| Avoiding Zone 1 via Blackhorse Road and Gospel Oak, with pink touches | £2.40 | £3.20 |
| Changing between the Tube and National Rail at Waterloo, Vauxhall or similar | £5.90 | £7.30 |
Fares read from TfL's single fare finder in November 2026. For two adults making the return trip off-peak, the pink reader is worth £4.80 for the day, unless a daily cap would have stopped the charges anyway. The last row is a reminder that the route matters in the other direction too: changing to a main-line train in central London costs more than staying on the Tube.
Two pink readers can be on one journey. Going from Walthamstow to Richmond via Blackhorse Road and Gospel Oak means two changes, and the fare above assumes you touched pink at both. Miss either and the system may decide you went through the centre.
Out-of-station interchanges: leaving the station without ending the journey
Some changes of train involve going out into the street. Camden Town Tube station and Camden Road on the Overground are a few minutes apart along Camden Road; the Central line and Overground stations at Shepherd's Bush are a short walk apart. TfL treats such pairs as an out-of-station interchange, usually shortened to OSI. You touch out at the first station, walk, and touch in at the second, and the system joins the two halves into one journey and one fare.
TfL gives its own example: a journey from Goldhawk Road to Earl's Court, changing between the two Hammersmith stations, is charged as that one journey only. The Conditions of Carriage put it as a rule: if you transfer between stations during a pay as you go journey, touch out at the first station and back in at the second so that you are charged for the full end-to-end journey.
Each pair has a time limit for the walk, and TfL publishes the whole list as a spreadsheet. The version available in November 2026 says "Data up to 01/03/2026" and holds 152 entries covering about 130 different pairs. Our page on Tube stations it is quicker to walk between deals with walking instead of riding; this list is about walking as part of a ride.
The walks visitors are most likely to make
| From | To | Time allowed |
|---|---|---|
| Camden Town (Northern line) | Camden Road (Overground) | 20 minutes each way |
| Shepherd's Bush (Central line) | Shepherd's Bush (Overground) | 20 minutes each way |
| Hammersmith (District and Piccadilly) | Hammersmith (Circle and Hammersmith & City) | 20 minutes each way |
| West Hampstead (Jubilee line) | West Hampstead (Overground) or West Hampstead Thameslink | 20 minutes each way |
| Hackney Central | Hackney Downs | 20 minutes each way |
| Bank | Monument, or Cannon Street Tube | 15 minutes each way |
| Tower Hill | Tower Gateway (DLR) | 15 minutes each way |
| Aldgate | Aldgate East | 10 minutes each way |
| Bayswater | Queensway | 10 minutes each way |
| Bond Street | Oxford Circus | 20 minutes each way |
| Euston | Euston Square | 20 minutes each way |
| Wood Lane | White City | 20 minutes each way |
| Canary Wharf (Jubilee line) | Canary Wharf (Elizabeth line or DLR) | 20 minutes each way |
| Southwark (Jubilee line) | Waterloo East (National Rail) | 10 minutes each way |
| Battersea Power Station (Northern line) | Battersea Park or Queenstown Road | 20 minutes each way |
Source: TfL's out-of-station interchange list, data up to 1 March 2026. The two Camden stations are the pair that matters most to visitors, because they connect the market and the Northern line to the Overground towards Hampstead Heath, Highbury and Stratford. Our guide to Camden Town shows where the stations are.
Why the Tube-to-main-line walk gets 40 minutes and the return 20
Look down the full list and a pattern stands out. Between a Tube station and the main-line station it serves, the allowance is usually 40 minutes in one direction and 20 in the other: Bank to Liverpool Street, Charing Cross Tube to Charing Cross main line, Euston Tube to Euston, King's Cross Tube to King's Cross, Tower Hill to Fenchurch Street. The longer figure is for the Tube-to-rail direction, because you may have to wait for a train that runs every half hour. Coming off a main-line train and onto the Tube, you only have the walk.
A few pairs are odder and worth knowing. Lancaster Gate on the Central line is linked to Paddington main line and to the Elizabeth line at Paddington, 40 minutes one way and 20 the other. King's Cross Tube is linked to St Pancras International with 30 minutes towards St Pancras and 20 back. Euston main line and St Pancras are also linked, which is useful if you arrive from the north at one terminus and leave from the other.
Going out and back in at the same station
Normally, touching out and back in at the same station starts a new journey. TfL makes exceptions where one station has several separate gatelines, and lists them as a "Same NLC OSI" (the NLC being the station's code). The ones a visitor might use:
- Oxford Circus: the Argyll Street exit and the main entrance, 10 minutes.
- Tottenham Court Road: the Central and Northern line gatelines, 10 minutes.
- Bank: the Central, Northern, DLR and Waterloo & City gatelines, 15 minutes.
- Waterloo: the Waterloo & City gates and the Bakerloo and Northern line gates, 15 minutes.
- Farringdon: the integrated ticket hall and the other entrances, 10 minutes.
- Paddington: the Tube gates at platforms 15 and 16 and the other Tube gatelines, 20 minutes.
- Highbury & Islington: the west end exit of the Overground platforms and the main entrance, 15 minutes.
- Richmond: the bridge and the lower concourse, 10 minutes, listed as step-free.
- Liverpool Street, Victoria and St Pancras main-line stations: between separate groups of platforms, 30 minutes.
Outside those listed cases, leaving and coming back in is two journeys. The Conditions of Carriage also say that if you enter and leave the same station without making a journey, you may be charged up to a maximum fare, so changing your mind at the gate is better done by asking staff to let you out.
What breaks a journey without warning
- Taking longer than the walking allowance. Stop for coffee between Camden Town and Camden Road and spend 25 minutes over it, and the second station starts a new journey with its own fare.
- Touching in at a station that is not on the list. Walking from one Tube station to a nearby one that is not a listed pair is simply two journeys, however close they are.
- Going over the whole-journey limit. The walk counts towards the overall time from first touch in to last touch out. Our page on maximum journey times gives the limits.
- Changing card or device. If you touch out of the first station with your phone and into the second with your watch, the system sees two different customers, and neither journey is finished.
- Changing to a service that does not take pay as you go. The Conditions of Carriage say you must touch out when you transfer to such a service, which ends the journey.
- The tram at Wimbledon, Elmers End or Mitcham Junction. TfL says you must touch out of the train and touch in again on the tram platform reader. The tram is a separate fare; see our page on the Croydon trams.
- A bus in the middle. Bus and Tube fares are never joined. The bus has its own Hopper fare, explained in our guide to London buses.
Paper tickets get far fewer of these walks. TfL's list marks most pairs "PAYG only"; only about a fifth also accept paper tickets, and six are contactless only. If you are on a paper ticket from a main-line station, ask staff before you leave the gates.
During closures the rules can stretch
TfL says it can activate out-of-station interchanges on an ad hoc basis to reflect unusual interchanges during disruption. When a line is closed and staff direct you out of one station to walk to another, the system is often set up to join the journey for you. Planned weekend work is the usual reason; our page on weekend closures and replacement buses explains how to find it in advance.
Checking that you were charged once
The proof is in your journey history. A correctly joined OSI journey shows as one line from the first station to the last; a broken one shows as two separate journeys, each with a fare. A missed pink touch is harder to spot, because the journey looks normal and only the price is wrong: compare it with the single fare finder for your route. If you were charged a maximum fare for something that went wrong at the change, our page on what happens if you forget to touch out explains how refunds work.
Frequently asked questions
What is a pink card reader on the London Underground?
It is a reader with a pink top on or between the platforms at 17 interchange stations, most of them on the Overground. Touching it when you change trains tells the system your route avoided Zone 1, so you pay the lower fare. It does not start or end your journey.
Do I have to touch out when I walk between two stations?
Yes. On an out-of-station interchange you touch out at the first station and touch in at the second. If the pair is on TfL's list and you arrive within the time allowed, the system joins the two halves and charges one fare for the whole journey.
How long do I have to walk between Camden Town and Camden Road?
TfL's list gives 20 minutes in each direction between Camden Town and Camden Road. Take longer and the second half becomes a new journey with its own fare, so save the coffee for after you arrive.
Is Bank to Monument one journey?
Yes. Bank and Monument are linked inside the station complex, and TfL also lists them as an out-of-station interchange with 15 minutes each way, so touching out at one and in at the other still counts as one journey.
What happens if I forget the pink card reader?
You are charged the higher pay as you go fare that assumes you went through Zone 1, or an extension fare on a Travelcard that does not cover Zone 1. You are not fined, but on a journey such as Walthamstow to Richmond it can cost over a pound more each way.
Sources
- Transport for London - Touch a pink card reader when changing trains (checked November 2026)
- Transport for London - Out-of-station interchanges (checked November 2026)
- Transport for London - Out-of-station interchanges list, data up to 1 March 2026 (checked November 2026)
- Transport for London - Conditions of Carriage, 24 September 2026 (checked November 2026)
- Transport for London - Touching in and out (checked November 2026)
- Transport for London - Tube and rail fares (single fare finder) (checked November 2026)