Basic pre-paid phone to buy for use in the UK?

Carphone warehouse have cheap PAYG mobile phones:
https://www.carphonewarehouse.com/mobiles/pay-as-you-go.html?intcmp=LP_MOBILES_QUICKLINKS_PAYG_210616#!/sort/p_t_upfrontprice

Also some Tesco stores:
https://www.tesco.com/direct/technology-gaming/pay-as-you-go-phones/cat3375958.cat?pageViewType=grid&sortBy=3&currentPageType=Category&catId=4294959890+4294959018&icid=mobilephones_textlink_slot2

Laurel, if you have an "unlocked" US phone that is tri-band or quad-band, you can easily buy up sim cards over here. As previous post mentioned, Tesco (grocery store) even sells them with reasonable data and voice plans. The WHS stores in Heathrow sell sim cards too. I think you have better rate options buying the sim card here than buying some international rate phone/card in the US.

Laurel,

The only reason to purchase a phone in the USA before traveling to the UK is convenience and peace of mind. But remember that you'll still need to go to a local outlet in the UK to purchase your SIM card for service. The 'international travel' SIMs you see in American airports are horrible deals and you're much better off getting a local pre-paid SIM card once you arrive.

That all being said, you will need an unlocked GSM Tri- or Quad Band phone. Most GSM phones produced in the last decade are Quad Band so this is rapidly becoming a moot point...

Do you use a smart phone at home? I can tell you from personal experience that having a fully-functioning smart phone while traveling overseas has dramatically enhanced my travel experience. Being able to perform travel planning (finding businesses, public transport and the like) in real time and at my fingertips is great.

I have also noticed that Sam's Club now sells unlocked "travel" smart phones at a pretty reasonably price.

As mentioned above if it's just a basic phone you want then you can't go wrong with one of the PAYG phones from Tesco supermarket.

If we fly in to Heathrow is there a shop that sells UK phones at the airport?