Say a friend on an E-2 visa pays ₩280,000 (approximately US$200) out of pocket after a late-night ER visit in Seoul. It's a useful example to walk through, because more than one process could apply here, and the right first move often isn't what people expect. Before contacting any government agency, call the hospital's billing office. If that doesn't resolve things, there are two other agencies worth knowing about: NHIS, which manages your coverage status and a narrow cash benefit called yoyangbi, and HIRA, a separate agency that reviews whether a specific charge should have been covered by NHI. Start Here: Check the Bill Before You Check the Agencies Call the hospital's billing office first and ask two things: was National Health Insurance (NHI) applied to your visit, and if not, why. That single call can resolve things entirely if the issue was simply that NHI wasn't applied correctly when the bill was issued. If the billing office can't fix it, sort yo...