Tesco Mobile - does call credit expire?

Say I have a Tesco Mobile phone and I buy €50 credit for it, but only make 1 phone call per week, say 50c per week. After 6 months I'll have used about €13 of the original credit, does he remaining €37 expire after 6 months (or whatever length of time?) or does it remain "credit" until used up.

Do I have to purchase a minimum amount of credit per month to keep my original credit?

see here:

http://www.askaboutmoney.com/showthread.php?t=94490

Thanks askU, answers all my questions! No Tesco mobile for me then.

As far as I know only the free credit you get has an expiry date, not normal credit. I'm actually on Tesco Mobile and I find I'm saving loads compared to Vodafone. I wrote a 'moan about tesco mobile' post a while back (referred to above by askU), but I'm still with Tesco mobile. For all their flaws, I still reckon they're probably the most cost efficient pay-as-you go provider.

Agreed. With their two for one offer and smart usage of their free credit Tesco Mobile offers the best value pre pay package.