Talk:United Kingdom/@comment-180.150.90.219-20180220024500/@comment-24682153-20180221100647

Well, this answer beats about the bush. It's fairly easy to get a UK SIM card from abroad. They are sold through Amazon.co.uk or eBay.co.uk or other channels. In the UK there is no registration of SIM cards. So the SIM already comes pre-activated. But you should need to go online, log on to your account and purchase a bundle or plan. For this you should register with the provider. Another major problem with UK SIM cards (except Vodafone) is that you can't top them up with a non-UK credit or debit card on their website. So activation is not a major problem.

But I agree with the comment that Vodafone UK may be one of your best bets. It includes Switzerland and you can top-up at least through PayPal.