Best international cell coverage for USA while in UK/Scotland?

I've used the Verizon internalal plan in Scotland multiple times in the last few years with no problems. Sure, at $100 for a month, it is not cheap, but I like that my phone works exactly as it does at home.

OP, you either need to provide more information, or do some research before asking a
high-level question.

The answers depend on things like 1) your current carrier/plan 2) model of phone 3) types
of usage you expect to want/need to have (to be able to translate into amount of
data consumption) 4) length of stay 5) level of tech savvy.

Without more input, you will get little more than general conceptual responses.

For those with Xfinity as their mobile service provider, the rules/fees recently changed. I used to pay $10 for a 24-hour period of time ($5 in Mexico or Canada) if I took my phone off air mode while in Europe. So I used to keep my phone in air mode for my entire vacation when out of the US to avoid getting charged $10 for a 24-hour period of data use.
I read the emailed notice from Xfinity about the changes earlier this summer but was sceptical.
Last month (July) from France I had to make 2 voice calls from France to the US. I did not get charged. My new bill posted yesterday is the same $23 including taxes and fees as it has always been.
Xfnity's site has a tool to enter the countries you will be visiting to see if they are included in its international data usage that has no charges.

Ditto Carrie. Verizon.

T-Mobile includes a good amount of international high speed coverage in some plans, notably those for those 55+. Or you can buy 15GB/month for $75.

I use a combination of the following:

Google Fi flexible plan:

• $20 for one line (I get to keep my original phone number)

• $10 per GB, both US & international (Bill Protection curbs maximum at $60; after 6 GB it's free)

• Free texts; both in The US and International

• Free calls in US/Canda/Mexico, $0.20 per minute for international calls

• Must activate and use it in the US for at least one day before departing abroad; can't do it abroad.

• Can't use it continuously abroad for 90 days or face data suspension.

Roamless flex plan:

• Pay as you go for data
• Generally around $2.45 per GB for Europe and the US
• Flex credit never expires and rolls over to future trips

Airalo eSIM fixed data packages:

• They have local, regional and global eSIM.
• Various GB and days combinations

I use very little data in the US as I use mostly home wifi, so I use Roamless when I'm outside my home. If I have a long trip abroad and plan to use a lot of data, then use Airalo eSIM fixed data package. Otherwise Roamless pay-as-you-go data will be my go-to choice.

I rely on Google Fi for domestic and international texts and calls.

P.S. I didn't take any trips last month, and my total phone bill was only about $25 :)

I second it! Verizon was easy peasy. Great coverage all the way.

Who is your current carrier in the US?

Who is your current carrier in the US?

This +1

Personally I'm on Verizon's Unlimited Ultimate plan that includes international travel.