Nothing wrong with SOAS MBA.

I am searching for an affordable online MBA from UK. But accreditation matters. So, I am wondering whether SOAS online MBA is as good as any other MBAs, for example Royal Holloway MBA or Msc simply because it is not accredited even by AMBA.

I think it really depends on your goal. The SOAS MBA is an MBA in name only: it's not a degree in general management or business administration. It's a masters in banking, as anyone can see from the curriculum, and would be impossible to accredit as an MBA. That's not the case, for example, with the Bangor MBA in banking, which has both the core MBA issues (people, marketing, strategy) and a strong banking element.

Of course SOAS isn't notable as a centre of business training, and I'm not sure how useful the alumni network would be. SOAS doing an MBA only for distance learning-bankers is a bit odd and, of course, there's no on-campus business school. The demand is there but, honestly, I think it would be a bit tricky if a SOAS MBA was actually appointed into an MBA-type role.

If you were actually looking for an MBA then, of course, you should take an accredited MBA. But if you want an MSc in banking then, what the heck, why not get one that's called an MBA?

Thank you for your advice, Duncan. SOAS "MBA" is a master degree specialised in banking. If I want a full MBA, I should do an internationally, by AMBA, AACSB or EQUIS, accredited MBA.

Yes, that's what I would recommend. And out of the accredited MBAs, get into the best one you can.