I am not a current student but I applied this year and I chose King's over UCL so I'll just give u a rundown of my reasoning.
1. Rankings : QS - UCL is 3rd in the UK 10th in the world, whereas King's is 4th in the UK 22nd in the world. Completeuniguide UCL 5th KCL 7th. My opinion on this is that even tho King's is just a few places lower this is actually King's coming out ahead because think about how King's psychology course is only a few years old ( This was the first year psychology at KCL was on the Complete university guide rankings and they were placed 7th) and yet its so high already, whereas UCL psychology course has been around for like 100 years.
2. not really a thing per say but..... UCL psychology is part of
'Psychology and Language sciences' whereas psychology at KCL is part of '
psychiatry, psychology and neuroscience' trivial i know but still
3. The Institute of Psychiatry, Psychology and Neuroscience is one of a kind, no other university in the UK (UCL included) has such dedication to the field, there's almost a whole campus (Denmark hill) dedicated to this, and you get to experience the research that goes on there first hand during your course. Also your 3rd year lectures are at the IoPPN and there is a module on the course where you learn about the actual research that goes on there which is sick.
4. KCL offers both a Professional placement year
And A year abroad, neither of which UCL have for it's psychology course. Work experience and general experience is pretty important for psychology and I feel like UCL - a university in London - the most connected city in Europe, a uni with such a high ranking for psychology doesn't have a placement year is weird. There are so many opportunities in London tho so maybe they felt like they didn't need to because you can just get work experience on your own, but having that dedicated year helps a lot. Also, KCL offers summers abroad too which are like years abroad but just in the summer - although I'm not sure if UCL does this as I havn't asked them.
5. The IoPPN offers Fellowships and Studentships to students who want work experience during the summer which is amazing as this is an amazing opportunity to work with the people who are leading psychology. The quality of this work experience is amazing compared to what you would get at another Uni. Although work experience opportunities at UCL are probably equally as good.
6. The graduate earningspage on Which? says that average earnings are 13k higher for KCL than UCL for psychology after 3 years. I have no idea why this is tbh maybe its to with that sick work experience lol
7. what I will say about UCL is that pretty sure intercollegiate is more accessible - especially the infamous Garden Halls, which are like right next to it. Also UCL has its main campus - whereas KCL is split into like 3 campuses, so i guess its more together if you know what i mean. Also, at UCL you get to do one credit module from another course, which I don't think you get at KCL.
8. when I got an offer from UCL, I was not invited to an offer holder day. This might not be a big deal but this was one of the reasons why I chose KCL over UCL. If they can't care about me enough to invite me to an offer holder day then this just leaves a bad impression for me... my 4 other unis managed to do this just fine - Also, the offer time was really really late compared to other Unis. King's was really fast in getting out decisions. UCL's response being that they have too many applications to go through just isn't cutting it for me, as every other uni manages to go through loads of applications without complaining, they are one of the best uni's in the world, yet they seem to be so unorganised.
9. student satisfaction is equally horrendous for both of them because they are in London, however, student satisfaction in psychology at KCL is really really high and its higher than UCL's course by a lot. This is according to completeuniversityguide
10. UCL's course is A*AA. KCL's Course is A*AA - but they offered everyone AAA which is a bargain.