Posted 12 hours ago
Wed 22 Apr, 2026 09:04 AM
Normally, every time you tap out of a Tube or train station, your journey ends and you get charged. Tap in somehwere else, and the meter starts again. But for certain nearby station pairs, the system makes an exception: tap out, walk to the nearest station, tap in, and the system recognises the two legs together as one fare. These are called Out-of-Station Interchanges, or OSIs.
They're not exactly advertised. The Tube map shows some of them as dotted lines, but doesn't explain that means, and plenty of OSIs aren't on the map at all. The difference can be pretty significant, for example:
Wembley Stadium to Barbican via Baker Street
- Without OSI -> £6.20
- With OSI -> £3.40
Finchley Central to Hampstead Heath via Kentish Town West
- Without OSI -> £4.20
- With OSI -> £2.20
OSIs worth knowing about as an LSE student
Key: NR = National Rail; LU = London Underground
Each one below comes up in a journey you're likely to take. Tap to expand for the details and we've noted which halls are closest to each interchange in case it's on your regular route.
If you’re on a Thameslink service, coming from Farringdon, St Pancras, Elephant & Castle, or further out, and you want to connect to the Jubilee line, this OSI covers the interchange. Tap out at Blackfriars National Rail, walk 600m to Southwark tube, tap in, and the system joins the legs as one fare. So it is either 40 minutes when going from the tube to a National Rail or 20 minutes from a National Rail to a tube.
The Journey: Anywhere on Thameslink ↔ Southwark/Bankside area
Closest Halls:
Bankside House and Sidney Webb House
These two share the same building, the tube platforms are below, and Thameslink runs through the upper level. There’s an OSI between them (40 min tube → NR, 20 min NR → tube), so switching between the District or Circle line and a Thameslink service doesn’t cost extra. Handy if you’re heading north toward Farringdon, City Thameslink, St Pancras, or south toward Elephant Castle and beyond.
Handy tip: If you’re heading to Bankside House and come in on the tube, you can walk across the indoor bridge rather than Blackfriars and not be charged twice, especially nice when the weather is particularly grim.
The Journey: District Circle line ↔ Thameslink
Closest Halls:
Bankside House, Sidney Webb House, and Rosebery Hall
Ten minutes for a very short walk. If you’re on the Jubilee Line and need to catch a Southeastern service from Waterloo East, heading to places like Greenwich, Lewisham, or further into Kent, this OSI means you only pay once.
The Journey: Jubilee line ↔ Southeastern trains from Waterloo East
Closest Halls: Bankside House and Sidney Webb House
Just 140m apart, one of the shortest OSI walks in London. Charing Cross mainline and Embankment tube are practically next door to each other. If you’re arriving on a Southeastern service and want to pick up the District, Circle, or Bakerloo line, this is counted as one journey. Walking distance from campus and High Holborn too.
The Journey: Southeastern trains from south/southeast London ↔ tube connections at Embankment
Closest Halls:
High Holborn and LSE Campus
One of the more generous OSIs, 40 minutes to the National Rail gateline and only 220m walk. If you’re on the Central, Jubilee, or Northern line at Bank and want to catch a Southeastern train from Cannon Street, this saves you a separate fare. The 40-minute window is long enough to grab food on the way, which is a bit of a bonus.
The Journey: Central/Jubilee/Northern line from Bank ↔ Southeastern from Cannon Street
Closest Halls:
Bankside House and Rosebery Hall
If you’re heading home on a Chiltern Railways train from Marylebone to Oxfordshire, Warwickshire, or Birmingham, and coming from the tube, this OSI covers the connection. Baker Street gives you the Metropolitan, Circle, Hammersmith & City, and Jubilee lines. The 550m walk takes about 7 minutes, and you’ve got a generous 40-minute window.
The Journey: tube ↔ Chiltern Railways from Marylebone (for home travel)
Closest Halls:
Carr-Saunders Hall and Passfield Hall
Euston tube (Northern and Victoria lines) and Euston mainline share the same building. If you’re heading home to Manchester, Liverpool, Glasgow, or anywhere on the West Coast Mainline, arriving at Euston tube and connecting to the mainline is counted as one journey.
The Journey: Tube ↔ Avanti/London Northwestern trains at Euston (for home travel)
Closest Halls:
Passfield Hall and Carr-Saunders Hall
Bond Street has the Elizabeth and Jubilee lines; Oxford Circus has the Central, Bakerloo, and Victoria. They’re only 280m apart and linked by an OSI, so if your route needs you to switch between these two stations, you won’t be charged twice. Comes up a lot on West End trips where your fastest route hops between lines.
The Journey: Any route requiring a line switch between Bond Street and Oxford Circus.
Closest Halls:
Carr-Saunders Hall and Passfield Hall
Two separate stations just 290m apart, linked by an OSI. If you’re switching between the Bakerloo or Northern line and Thameslink or Southern services at Elephant & Castle, you only pay once. A useful hub if you’re travelling between South London and Central London regularly.
The Journey: Bakerloo/Northern line ↔ Thameslink/Souther services south of the river
Closest Halls:
Robeson House
What about the Thames Clipper?
Short answer: no, OSIs don't apply to river buses. You can use Oyster or contactless on Uber Boat by Thames Clippers, and if you’re in Bankside or Sidney Webb, the pier is right there, but river travel sits outside the normal Oyster system. The daily cap doesn’t apply, and there are no OSI links between piers and tube stations. It’s always its own separate fare.
How to make sure it works
💳 Use the same card for both taps. Mixing Oyster and contactless, or switching devices, breaks the link.
⏰ Watch the clock. Time limits vary: Southwark LU ↔ Waterloo East NR is only 10 minutes; Bank LU ↔ Cannon Street NR is 40. Check before you rely on it.
‼️ Tap out properly at the first station. If you forget, you’ll be charged a maximum fare and the interchange won’t register.
👉 Check your journey history on the TfL website afterwards if something looks off; TfL customer service can usually sort errors out.
Full list: The independent Oyster Fares website has every OSI in London with time limits and walking maps. Well worth bookmarking.
Heads up: OSI rules can change, and time limits sometimes differ by direction. Always double-check before planning a journey around one.
