High Speed One supplements: London <-> Ashford International

[shinkansen1966]

Exactly what are the one way and return supplements for travel on High Speed One both with and without a Network railcard ?

South Eastern web site does not appear to publish a list of supplements.

For instance, I'd like to make a return trip from London to Folkestone, travelling on HS1 in one direction only with a Network Card. National rail does appear to offer this option either.

I'll buy the HS1 supplement with Network Card before boarding the train.

 

[Be3G]

The possible non-discounted upgrade fares for that journey are:

Off-peak return: £5.10
Anytime single: £5.30
Anytime return: £5.60

I assume you're au fait with the Network Railcard's time/minimum fare restrictions, so I infer that you plan on travelling off-peak. In which case, it looks like the off-peak return upgrade would be cheapest, even for a single journey, which with a railcard discount comes to £3.35.

All of that information was found from brfares.com – a wonderfully useful site, if you know what you're looking for.