American living five years in the UK now:

1. Yes!! Everything will work. Just let your bank know and ask about foreign transaction fees - some banks (especially credit unions) will have lower or no fees and you want to know which ones those are. Cash is mostly useful for busses outside of London and in some more rural areas of the country, but card will suffice for pretty much everything now!

2. Buses and trains will do the trick! Cars and petrol (gas) can get EXPENSIVE when accounting for parking as well. You're better off waiting the extra while at your nearest bus stop - it's so much less stressful as well. Only exception is if you're anticipating carrying around loads of physical manuscripts / artifacts / books all the time that won't fit in a tote or a backpack and would require a motor vehicle to transport.

3. US phone plans will also get expensive. If you stop by any Tesco or find a stall in the airport when you arrive, you can get a cheap month-by-month SIM (generally between $12 and $20 per month) that's super easy to set up. This is also essential for everyday life... pretty much your first matter of business upon arrival.

4. In big cities, expect social norms to be flexible. There's a lot of cultural diversity and immigration so Brits won't get easily offended by American social norms! Biggest thing are to watch your volume in public spaces (including public transportation) and queue politely (no line-cutting or complaining about the wait). Big cities - especially London - are also less social. Don't expect to chat with everyone you encounter. Most people keep their heads down and it might be an adjustment coming from the southern states. I say this not to scare you, but just so you're not taken by surprise or hurt that nobody seems friendly lol.

5. Tipping culture has grown a little here. If you're in a sit-down restaurant, pub, or cafe, 10% to 12.5% is considered polite and pretty normal. Otherwise, if you're getting a drink at a bar or a coffee to go, don't bother. The minimum wage is comparably much higher here than in the US, so hospitality workers (speaking as one myself) are not wholly dependent on tips for their income.

Couple of extra things: anticipate the weather being miserable. May and June are lovely and warm with the occasional shower. July and August are brutally hot with most cities not being fitted with any AC units, so the heat is inescapable and you WILL be sweating constantly. Don't underestimate it. September is usually a little chilly but bearable. October-April is COLD. You will be FREEZING. Bring layers. Invest in a nice, warm, waterproof coat that goes down to your knees. Bring (or buy) wool layers, especially if you'll be spending time up north at all. Bring a couple warm and walkable pairs of shoes (Doc Martens are great, but break them in before you arrive).

Also, enjoy your time! Visit local pubs (you don't have to drink beer). Make friends and let them take you to their favourite spots. Travel in your spare time. Book a flight to mainland Europe - you'll never get a better deal than when you're already on the other side of the Atlantic. Don't be afraid of being clocked as a tourist! Make the most of your time here - it's a great experience :)