London Thameslink ticket valid via underground?

[reduke]

My memory may be failing me, but seem I remember reading something a while back that implied that Thameslink tickets from the MML to London Bridge were also valid for travel via West Hampstead to London Bridge on the underground.

Was I mistaken or correct? And if correct, is this still the case?

If mistaken or not still the case, if I was to arrive at West Hampstead/STP and the core was out of action due to unplanned disruption, are there any legitimate means of reaching my destination other than paying extra and claiming delay repay?

Thanks!

 

[Dirty_Mac]

That seems to be true at least according to this https://www.railforums.co.uk/attachments/nr-lu-interavailability-pdf.18694/

 

[reduke]

That seems to jog and fulfil the "memory" section of my post, thank you!

Now to find out if there is a current version somewhere - ie not including the words first capital connect!

 

[eddp]

There's a Freedom of Information response here with a list of the current (well, November 2025) interavailable routes, Kentish Town (not West Hampstead) to London Bridge/Moorgate/Elephant & Castle is listed which also aligns with my recollection (that these tickets can be used to/from Kentish Town via the tube, but not to West Hampstead). It's interesting that there seems to be some disagreement about whether West Hampstead is actually included here or not.

 

[MrJeeves]

TfL's "Book 2 - Ways to Pay" internal document, released under FOI, details the interavailable routes in further detail, and explicitly include West Hampstead. Interavailability is limited to only Tube stations where Thameslink services also call, and not any intermediate stations.

TFL list of interavailable routes for National Rail tickets.

Does anyone have the full list of TFL interavailable routes? I remember seeing an official document years ago listing all of them but i can not find it now. I recall that National Rail tickets are valid on certain London Underground routes (and possibly certain Docklands Light Railway and...

www.railforums.co.uk

The main thing to point out which hasn't been mentioned yet is that any tickets routes "Thameslink only", "Not Underground" or "London Not Underground" do not have any interavailable validity on the Tube.

Thameslink interavailable routes: West Hampstead - Kentish Town – St. Pancras International /King’s Cross St Pancras - Farringdon – City Thameslink- Blackfriars LU/NR- London Bridge - Elephant & Castle

LU/DLR issued station of origin tickets can be used on National Rail services at intermediate stations. Tickets printed for travel between “London Thameslink” and West Hampstead (and stations north of West Hampstead) are valid on Tube services between the Thameslink interavailable stations, but not at other intermediate Tube stations. Tickets printed for travel between “London Terminals” and Bedford (and stations north of Bedford) are valid on Tube services only between Kentish Town and King’s Cross St Pancras, and not at intermediate Tube stations. The following are not valid on Tube services: Tickets with a printed route “Thameslink Only”, or “Not Underground” or “London Not Underground” Tickets issued to “London Terminals” from stations south of the Thameslink interavailable route

 

[reduke]

Thank you MrJeeves!