Advice for switching PhD programs back to my undergrad field I'm a first-year PhD student who switched from field X in my undergrad to field Y at my current university. The program I'm currently in is ranked #1 in field Y. I am genuinely unhappy here and am looking for advice on switching programs. 

I joined this program because I had done research here before and enjoyed it, and it's an excellent university, so I figured it'd be a no-brainer. I was a little worried about switching fields, but everyone said things like "classes don't matter" or "choose the PI, not the school", so I figured this decision would be best. Unfortunately, I was mistaken.

I'm quickly learning that I do not have interest in many of the required courses (I think I wrongly convinced myself that I would), and there is a large amount of classes I need to take (about 12). I'm not enjoying the material I'm learning, and I'm also finding that I don't have many pre-requisite classes I need to truly excel and understand the material. I am sitting in on lower-level classes and giving it my all, but this is just adding on more and more time between myself and what I want to do -- research.

In all, I do not find myself happy here. I am very passionate about research still, and I think pursuing a PhD in my undergrad field at a different institution would be a better fit for me. 

Does anyone have any advice about how to do this most effectively? I plan to be up-front with all those involved, and I intend to briefly but clearly explain why a new program would be a better intellectual fit than my current one without bashing my current university. I can get a strong letter from someone at my current university, although he is actually in the field I want to switch to, not the one I'm currently in. I hope my letters writers understand if I explain my scenario to them. 

I imagine this will be a sticky situation, since I doubt I'll be funded to stay in the program next semester if they know I plan to leave, and I'm definitely not going to pay out of pocket. But I'm not going to lie by omission! 

If anyone has been through this process, I would be eager to hear any advice. I just want to do this in the best way possible, for myself as an applicant and for others involved. I plan to re-apply to some universities I got accepted to in the past as well as other universities I didn't apply to before but think would match my interests.
I understand your concern about spring semester funding.  Why don't you put in some applications and wait until you get an acceptance before informing your current department?

I think your department will be glad you've got the self-awareness to realize when something isn't working.