Tipping

Tipping for good service is more common in the USA than in the UK, but there's surprisingly little consensus about when and how much to tip.
You should probably tip:

• In restaurants.  Really.  On at least one occasion, a restaurant called the police, and they came. 15% minimum. Be careful, as they might automatically add a tip to a large party (but you might still consider throwing a couple more dollars in there.)
• Taxi drivers.  15% - sometimes this is automatic (e.g. if you pay in advance).
• The postman is allowed to keep a tip of up to $20 at Christmas.

You should probably not tip:

• Take out food.  Unless they did something really special.
• Gas station attendants.  In some states there's always an attendant.  In others, you have the choice of self-service or full-serve.  The full-serve will cost you more (but they'll clean your windscreen and check your tyres and oil).

Eating Out (and Tipping) in the US

Americans eat out more than British people, and Americans go out for breakfast more than Brits. Here are some random facts.
Portions are often (not always) larger than you might be used to. It's fine to ask for it to be boxed up to take home.  Every restaurant I've ever been to does take out, so they will have boxes.  It's not weird or embarrassing to ask - it's so normal that if you have a substantial amount left that you haven't eaten, and you don't want to take it home, the wait staff will assume there's a problem.
Tipping. You know this already if you know anything about America. You have to tip. 15% is minimal - that means it was just about OK.  If you go to anywhere regularly it's worth your while to tip at least 20%, and you won't have to go there that regularly to be remembered - you'll be the person with the British accent after all. (In one restaurant near me, I'm the white person with the British accent. I hadn't been in there for about 6 months - I walked in and they said "Hi Jeremy, did you move?"
Soft drinks and coffee will usually be refilled for free.  You keep drinking, and they'll keep filling.  This can lead to a lot of bathroom breaks.

Schools in American

I've been thinking about what to write here for a long time.  The trouble is that states control a lot of education, and so it's very, very variable from state to state.  No Child Left Behind introduced standards which all children were supposed to achieve, but what the standards were (and what the subjects that would have standards were) was all left to the states. 

American Healthcare

I'm not even going to try to start to explain that.

Oh all right then, but not much. It's very complicated. You have to pay, but no one knows how much. Not even the doctor or the dentist seems to know how much until several days after you've left, when you either get a demand for more money, or a check because you overpaid. Or sometimes both. On the same day.

You'll have health insurance (probably). That means that they'll pay for some doctors (in network), and they'll pay less for other doctors (out of network) and they won't pay some doctors. Your health insurance will cost you, or more likely your employer, a lot

Holidays / Vacations in the US

A holiday isn't a time off work - it's a special day. Mother's Day, Halloween, Thanksgiving, etc are all holidays. Even if you go to work.

Mother's day isn't the same day as the UK, but you'll have problems missing it.

Halloween is big on trick or treating (obviously). When it comes to halloween, the rule is that if you have your porch light on, you'll be expected to give out candy. If you're after candy, go to the houses which have their porch lights on. People dress up at halloween, but you are allowed to dress up as anything you like - it doesn't need to be halloween related, as long as you are dressed up. People often dress up at work, again, it doesn't matter what you dress up as.

Thanksgiving is a big thing - it's a 2 day event, making 4 days of festivity. People traditionally go home to their families, causing all kinds of travel chaos around that time. Avoid going on any road trips, or airports, around that weekend. The nice thing about thanksgiving is that no one needs to worry about 'the real meaning of thanksgiving'. The real meaning of thanksgiving is to sit around, eat, drink and (possibly) watch (American) football on the TV. Which leads to ..

Christmas is a much smaller thing than in the UK. My theory is that this is partly because of thanksgiving. You've just had a holiday which involves sitting around eating, drinking and seeing family, so it feels strange to have another devoted to the same thing - particularly when there is more religious belief amongst christians (who might need to worry about the true meaning of Christmas) and more non-Christians, who don't worry about Christmas. Boxing Day doesn't exist, and it's not a holiday. You go back to work on the 26th. Places don't close much at Christmas - you can go to the movies, lifeguards work at the beaches (I know this, because we were admonished by a lifeguard for being on the beach after dark, when it was supposed to be closed.)

As in the UK, there are a few other days scattered around where you don't go to work. The complication is that some of these are 'federal' holidays, which anyone who works for the government gets off - that means no post, no school, etc, on those days. But everyone else has to go to work.

Here's a list:

1st Jan: New Year's Day.

3rd Monday in January: Martin Luther King day (Federal holiday)

3rd Monday in February: President's Day (Federal, I think)

Last monday in May: Memorial Day

First monday in September: Labor Day

2nd Monday in October: Columbus Day (Federal)

November 11th: Veteran's Day (Federal)

4th Thursday in November: Thanksgiving

25th December: Christmas day

American Language

We speak the same language, in theory, but we use a lot of different words. You can read about these in books, or look them up on web pages (like this one) , so I won't bother to list them. You will, however, forget, when you are put on the spot. So try to be prepared. Before buying petrol, remember that it's called gas. The one to really watch out for is chips. Chips are crisps, if you want chips, you need to ask for fries. You can know this, but it will take at least one disappointment before you remember for good.

Swearing

You should obvious be as careful (or careless) about offending people as you would be in the UK, but there is a little variation. The word piss, or pissed, especially to mean annoyed, is not as offensive as in the UK. The word twat is more offensive.

Getting a Credit History in the US

A problem I have already alluded to is your credit history. Without a credit history, there is a lot you can't do. But it's hard to get a credit history, because you can't do stuff to get one. Some providers will give you a really rubbish credit card, where you are required to put money into an account, and then they will let you spend it on your credit card. But it gives you the beginning of a credit history.

There is quite an art to getting your credit score higher. Having credit cards, or loans (which you pay back) or bank accounts helps. And the longer you have them, the better. Having credit cards that have lots of clear balance on them helps too - the more spare balance on your card, the better. BUT you have to use the card a bit, to show that you can use it and pay it back. The ideal (I read somewhere) is to use 35% of your credit limit each month, and then pay it back.

But, don't apply for credit cards to try to get a better score, because every time you apply for a card, they run a credit check on you. And every time they run a credit check, it hurts your credit score a little. I have an American Express card, and I realised that my credit score was hurting because I was using it each month (it was a 1% cashback one), so I applied for a higher credit limit. I'd had the card for 6 months, and had religiously paid the balance every month - in fact, I was so scared of a black mark that I paid it almost weekly. When I applied for a higher limit, they didn't take this into account, they ran my credit score, which came back saying that my balances were too close to the limit on my credit card, so they wouldn't give me a higher limit. (But I wanted a higher limit...)

Then I applied for a mortgage, and found that the credit check American Express had run had knocked my credit score just enough that I couldn't get the mortgage I applied for (and because I'd applied, that was another hit against my credit score. Aaaghhh!)

In theory you can get your credit score once per year from the credit agencies, Experian, Equifax and TransUnion. They don't make it especially easy though. I now keep track of my credit with TrueCredit, which costs $15/month, but lets me keep an eye on it.

Insurance companies and prospective employers might also run a credit check, to see what kind of person you are.