Arriving in the UK
I suggest arriving a minimum of 3 days before the move in date to give you time to open a UK bank account and buy any items you need for your accommodation. You will need a UK address and proof of acceptance to college to open the bank account.
Fitting out the dorm room
Your child will only be able to take a limited number of personal items with you such as a laptop, phone and clothes. The UK main voltage is 240 so make sure to check the chargers for dual voltage 120/240V. Most laptop and phone charges are dual voltage so you will only need a UK adaptor plug for these to work.
The college website generally provides a “What to bring” list, York St. John’s here (link).
If you are in self catered accommodation you will need to buy some kitchen appliances, pots and pans and cutlery. If you have been communicating with other housemates you might be able to split these up between you. No one want 5 toasters.
One of the best places to shop for almost all the items is the Walmart owned “Asda” store.
Grocery prices in the UK are cheaper than US and there is so much competition keeping the prices lower. Asda, Morrisons, Sainsbury’s, Tesco, Lidl and Aldi are just a few of the stores available, and they even provide delivery for a low price.
Asda has a delivery plan for £5 or £6 (link) a month for online purchase and are delivered for free. There are some limitations such as only one delivery per day and a minimum order of £40 but you could easily club together with others in your house and dorm to make sure you hit that amount.
We spent around $300 for everything my daughter need for her room and kitchen. I did additionally buy her a Cannon printer for £50, and replacement inks from Ebay.co.uk.
Mobile Phone plan
The UK phone plans are cheaper than in the equivalent US plan. There are many more mobile providers. One such provider with a good deal is Virgin Mobile. A monthly plan (SIM only), bring your own phone, and yes US phone do work in UK, can be had for as little as £9 ($12) for unlimited texts and 5GB data (link).
Cost of Living
One thing you can have you child do for the first few months of college is to log every penny they spend, and I mean every penny. Kids do not realize how much they spend until they write it down and they will be surprised how much they spend and where it goes. My daughter is self-catered so she has to buy and cook all her food. She has been at college now for 3 months and she is faithfully documenting her spending so we could determine how much money to send her each month. Right now it is around £145 ($200) per month. We have been transfering money over to her UK bank account using an online service. I researched a couple of sites who allow you move money from US to UK bank accounts and TransferWise (link) was my favorite as it had the lowest fees and a good exchange rate. I have only used it a couple of times up to now and it was really easy and the money arrives in 2 hours.