I am currently in the USA and having to remember my US etiquette. There are a number of things that are different on this side of the atlantic that can surprise a British diner.
You have to remember to hang on to your knife and fork in all but the poshest restaurants. You get one knife and fork and it has to last you for your starter and main course. If you ask for side salad, don’t be surprised when it comes before the main course. It will often be assumed that you want it as a starter.
Also, don’t be affronted when your fellow diners have their plates whisked away when they are finished, even if you are still eating. Removing a plate before everyone is finished may be a ‘no, no’ in the UK but not in the USA.
When the bill comes, things are a bit different again. Whereas here a tip is usually 10% of the bill if you are particularly pleased with the service, in the USA the norm is 15% and it is customary.
So, when the bill arrives you either add the tip to your credit card (or leave it on the table in cash as at home). You then sign the bill and usually you are expected to go once you have left the signed credit card statement on the table.
America does not use PIN numbers for credit cards, but you may be asked for photo ID. Extraordinarily, hardly anyone ever checks your signature.
Finally, on this trip it seems that the portions in the USA have become a little less gargantuan than in the past.
However, it is still quite acceptable (and wise practice if you don’t want to be totally stuffed) to agree a dish with your fellow diner and ask your server to “have that to share”. We have always found that to be accepted as normal and an extra plate and cutlery is brought as a matter of course. Sometimes the dish will be expertly divided between two plates!
Also, if you are watching what you eat, check the dietary information provided by the chains. My choice of main course in one restaurant was very quickly changed when I read that it contained 126 grammes of fat!
Finally, America is ruled by franchises. That means that, wherever you go, there is a recognisable name that you may want to choose. However, it does also lead to franchise standards and a lack of individuality.
I recall, once, sitting in an Outback in Illinois having flashbacks to the previous Outback in Florida. In every way they were identical. In fact, didn’t I recognise the waitress?