I am trying to find two tickets from London to Paris, one way, on Eurostar for June 22. As far as I can tell, the cheapest ticket on www.eurostar.com is 149GBP per person. Is there any other less expensive option?

Try flying (BMI -- flybmi from Heathrow) or check whichbudget for other airlines.

Buy r/t on Eurostar and don't use the return.

$90 thru RailEurope - valid on trains Mon-Thu between 11am and 3pm - cheaper than the day return of $94 - if you're under 26 it's $45 one way. My advice is to call BETS (800-441-2387) for info and expert advice - they're a RailEurope agent and extremely helpful. Raileurope has a $15 booking fee. However these fares are in limited availability so act soon.

If you book a roundtrip ticket with a Saturday night stayover, or a return trip in the same day late at night (with outbound trip early in the morning), you can get it for 70 GBP (leisure fares). You don't have to use the return ticket, but you won't get a refund.

Re flying..if you do THAT, please add in the money, and TIME, you'll spend getting to and from the airports and when these "I'd never take a train" people who hang out here start in with the "RailEurope is a rip-off" routine remind them that it isn't always the case..unles you really want to pay 70GBP instead of 90 US dollars!

I found it cheaper to buy a return and simply not use the return journey.