Note about council tax for US students living in UK

Maybe I wasn't clear in my post. Our interpretation of the rule was 21 hours of tuition, and this doesn't include private study time. If you've been granted an exemption based on private study hours you can consider yourself lucky. To be considered full time your university would have to clearly state that you are doing 21 hours minimum per week, this could be as work placement or classroom based study. It cannot include private study time.

If the rule were simply 21 hours of study per week then part time students could be exempted.

This isn't at all private study time - I'm being supervised both by my advisor in the States & a supervisor here in the UK, as I'm preparing to defend my dissertation proposal & then continue writing my dissertation. 

If the UK council tax system generally does not allow for research students (or the US equivalent - which is an "all but dissertation" graduate student) to be counted as students, that's pretty sad.  Especially considering that most UK humanities doctorates (not sure about science ones) are entirely research-based.  It's very difficult to hold a job that pays enough to support one (in addition to paying tuition/fees!) while writing a dissertation.  In fact, in order to even hold non-university employment, I'm required to get approval from the fellowship office at my university!

Just my opinion on that, though. 

Especially considering that most UK humanities doctorates (not sure about science ones) are entirely research-based.

Yes, UK science doctorates are 100% research - when I was an undergraduate exchange student (in physics) in the US a few years ago, I was very surprised to discover that the PhD students there actually had to take classes!! 

In fact, in order to even hold non-university employment, I'm required to get approval from the fellowship office at my university!

I assume that's because the majority of British doctorate students are being paid to do their research/write their dissertation and so are already considered to be working full-time and being paid for it. One of my friends has just started his PhD and, because he is being paid in Euros via a foreign research council, the exchange rate means that he is currently earning £20,000 a year just for doing his research... that's a good few thousand pounds more than my current full-time retail job pays, yet I have to pay council tax and he doesn't!

To be considered full time your university would have to clearly state that you are doing 21 hours minimum per week, this could be as work placement or classroom based study. It cannot include private study time.

According to the various university and government websites I have just looked through, PhD students are exempt from paying council tax for the three-year duration of the degree even though they don't take any classes. However, if they are in the writing-up stage of their PhD and have gone over into a fourth (usually unfunded) year, they will have to pay council tax, as they are no longer part of the 3-year full-time PhD course.

According to the various university and government websites I have just looked through, PhD students are exempt from paying council tax for the three-year duration of the degree even though they don't take any classes. However, if they are in the writing-up stage of their PhD and have gone over into a fourth (usually unfunded) year, they will have to pay council tax, as they are no longer part of the 3-year full-time PhD course.

This is probably what I have come across at the council. Obviously, if your university gives you a certificate of full time student status the council aren't going to question that, and the discount or exemption is applied. It's the students without this certificate, such as students from US universities doing independant research over here, who generally end up in front of a council tax officer trying to prove their status.

What I was trying to get across in my post was that if your situation is similar to the OP, you are going to have a hard time proving that you are a full time student. Most council tax officers won't make the decision that you are a full time student without a UK university  backing up the student status. Of course there are always exceptions, but you shouldn't count on being exempted.

Then, sorry to say, that was an incorrect interpretation, and not in accordance with the legislation laid down by central Government.

Above we have been provided with a link to the Harrow website. I think that correctly sums up the situation.

The guidance from the Harow website could be misleading. 21 hours of study per week is not enough to classify a student as full time on its own. As I said before, many part time students and distance learning students easily meet this minimum of study time but are not exempt.

I think this webpage from the Birmingham City Council website correctly states the law in this area.