Someone made a comment about how Korea and America had the same cost-of-living, and I responded rather strongly, but then realized it would probably make a decent blog post.
As a teacher in the U.S. (especially now that I have my master's degree and live in the DC metro area), my salary would be more than $50,000/year (substantially more if I taught extra test-prep classes, which I sometimes did). This is about twice what I earn in Korea (Currently base salary is 2.4 million/month, plus a lot of money from the after school classes I teach and extra duties, like writing essay prompts for district contests or interviewing for high-up positions in the BOE, which at the current exchange rate works out to USD $26,000 with the end-of-year bonus), and while housing being covered in Korea makes up quite a bit of the difference (I pay less than $40/month in rent for my posh new apartment), there are still major ways that Korea's COL beats out America and makes it easier to live a good lifestyle here.
Things that are cheaper:
--Transportation: Public transit is cheap and excellent. Even if you decide to get a car or scooter, gas is more, but insurance and maintenance are WAY less.
--Health insurance: Medical costs here (unless you get cancer, which is not covered by the National Plan) are cheap, cheap, cheap. I have a chronic condition that requires 6 pills a day of one medication, 2 of another, and monthly doc visits with a specialist. My monthly medical costs? About $30--this includes my birth control pills.
--Utilities: Gas is cheap, except sometimes in winter if you blast the floor heating, and electricity is cheap, unless you blast the AC in summer. Cell phone is about the same, but high speed internet is WAY cheaper, as is cable.
--Hobbies and activities: I pay ~$80/month for DAILY tkd, in the US I'd be lucky to find a studio that did three days a week for that price. I pay $5 at my swing dance bar, in the US I usually have to pay $10-$15 for the same thing. Skiing is cheap for skiing (about $70 for rental/lift pass for a day). The only thing I've heard might be a LOT more is golfing, but I don't have that particular vice. Gyms are about the same price.
--Dining out: A decent meal out costs between $7 and $20/person, drinks included, NO TIP. Home delivery is cheap, cheap, too.
--Taxes: Comparing the 3-5% I pay here with the 30% back home? Please...
However, living abroad has taught me that there are a lot of things I thought were "necessities" that are not actually necessary, like bathtubs and clothes driers. When I come back to the U.S., I might not be inclined to pay out the behind for cable services and snazzy internet, when I will have access to those things from the library or my parents' house. I will definitely be living cheaper than I did (and I lived pretty frugally before).
I hope that helps some of you folks thinking about expenses in Korea.