It always cracks me up just how heated these debates get on what a person can or cannot live on in Bangkok (or Thailand in general). And of course people frequently have these same arguments when it comes to what a “livable wage” is in their own countries as well.
For example I constantly get into heated arguments with my sister over her insistence that it is not even in the realm of possibility that she could ever afford to move back here to California - where she was born and raised by the way. This despite the fact that millions of people manage to live here just fine while making even less money than she does.
In any case, naturally you CAN live in Bangkok on 30K a month. After all, there are currently millions of people doing just that. For a foreigner living in Bangkok however I think the real question is; is 30k enough to live in the manner to which you have become accustomed back in your own country? And I think the answer to this question for most people would be a resounding “NO”.
Living the same as you do back home of course means that you live in an apartment or house that is just as nice and just as large as what you had back home (and in as nice an area). It also means having your own car, or at least a motorcycle, and being able to pursue all the same hobbies and other interests that you enjoyed back home. For me personally this would mean making an absolute bare minimum of about 60,000 baht a month, which is about what you would earn per month working a 40-hour a week minimum wage job here in California.
And of course, since I have spent pretty much my entire adult life living on the coast, this means I would need to live on the coast in Thailand as well and unfortunately properties in coastal areas in Thailand are extremely overpriced relative to the Thai economy. In fact, condos in Patong or Kata Beach in Phuket cost nearly as much per square meter as they do right here in idyllic San Luis Obispo, California. When my girlfriend and I were living in Phuket we actually got by fine on 60k a month but we were also not able to put anything aside for emergencies. And we certainly did not have enough money to travel around Asia much or to buy any luxury items.
The bottom line is, if I were forced to move to Bangkok with only 30k a month to live on I could definitely make it work. But I would never in a million years CHOOSE to move to Bangkok with only that much money to live on.