OK, I've got to go to the UK for a little while and I need a pre paid SIM card. Now last time I was there for only 3 days I purchased a Mobile World (or similar) card from Carphone Warehouse which gave reasonable rates back to LOS (say 15p a minute) and ok local rates (say 10p a minute) for a 3 day stay but if I am there a few weeks then these costs are too high.

So what is the best deal ? More interested in calls than texts, most likely daytime but I need options to call back to LOS. Are we looking at calling cards here as I have no experience with them ?

Not bothered which network, central London so I suspect they all work.

I would google 'cheap calls to thailand' find the cheapest 0845 rate that routes calls to thailand then find out which network does the cheapest calls to a 0845 number but to be honest i thing they sting you....

if you call from a landline instead alot of these 0845 numbers are like 2p per minute from a landline

Thanks for that but on Pre paid I think you are right. I was just hoping someone had done the homework recently.