Property tax is not set by the market price — three layers: official price, fair market value ratio, tax cap

Two people in the same neighborhood own apartments worth the same ₩500M, yet their property tax bills differ: ₩504,000 a year for one, ₩684,000 for the other. The market price is the same; what differs is whether the home is that person's only one. Property tax is not set by the market price. It is a three-layer calculation that starts from the official price, multiplies by the fair market value ratio, and picks a rate table. Most people just pay the amount when the July bill arrives, and because they do not know where each number came from, they would not notice a mistake. It is commonly thought of as some percentage of market value, but market value never enters directly.

Step ② The fair market value ratio. The rate is not applied straight to the official price; 60% is applied first to give the tax base. An official price of ₩500M gives a tax base of ₩300M, ₩300M gives ₩180M, ₩900M gives ₩540M. The ratio is set by law, so a local government cannot change it at will, and when the government lowers it by decree for a year the tax base drops further. That year's ratio is printed in the calculation on the back of the bill. The distance from market widens twice, so a ₩500M market home comes down to a tax base around ₩200M, and a lower base lands in a lower bracket of the rate table, so one ratio changes the bracket too. In a year the ratio rises, the same home's tax can jump twice, and someone who applies the rate straight to the official price overestimates the tax and hesitates to buy.

The year's tax is paid in halves in July and September: 16 to 31 July and 16 to 30 September, all in July if ₩200,000 or less. A second bill in September is not double taxation; the land portion is added then. Above ₩2.5M a split is available, the excess up to ₩5M and half above ₩5M deferred two months, applied for within the deadline, with a surcharge after it. The worksheet is three lines: ① official price and the 1 June owner, ② tax base and that year's ratio, ③ special-rate eligibility and the two dates. With those three, property tax preparation is done and you only check the bill line by line. Make the sheet once and change the numbers each year; the urban area portion and regional resource facility tax sit on the same bill, so the total exceeds the main tax.

All three steps are passed: start from the official price, multiply by 60%, and the special rate for a one-home ₩900M or less. The same ₩500M split into ₩504,000 and ₩684,000 on whether it was the only home. Not knowing 1 June means paying someone else's tax, not knowing the special rate costs ₩180,000 a year, and missing the deadline brings a surcharge. Two things to do now: mark the official price, the 1 June owner and the objection period on the spring calendar, and check the July and September bills line by line. That year's ratio and the extension of the special rate are decided by decree and the Assembly, and as of 2026-09-05 the extension has not passed. Property tax is set by three layers: official price, ratio, rate table.