MoneyLog｜부동산·경제 인사이트

During client consultations, I hear this question far more often than you might expect.

“I won a property at auction and plan to sell it quickly.
Everyone around me says I should register as a real estate trading business.”

This advice is only half right.
The real problem is that many people register without fully understanding why they should do it and when it actually works in their favor.

In one real consultation, a client reduced capital gains tax by registering as a trader, but later faced unexpected health insurance premiums that wiped out most of the benefit.

On the other hand, I have also seen investors pay far more tax than necessary simply because they did not register and could not deduct legitimate expenses.

This article is not about saying “yes” or “no” to becoming a property trader.
It is about explaining who truly benefits — and for whom it can trigger a serious tax burden.

By the end of this article, you will at least avoid making a costly decision based on incomplete information.

Key Advantages of a Property Trading Business

For short-term property investors, the biggest difference lies in how profits are taxed. Registering as a property trader fundamentally changes the tax structure.

Tax Structure Comparison

Individuals selling within one year face a flat 70% capital gains tax, while registered traders are taxed under progressive income tax rates (6–45%).

Expense Deductions

Traders can deduct a wide range of business-related expenses such as eviction costs, loan interest, renovation expenses, and brokerage fees.

Financing Advantages

Compared to individuals, traders often face fewer DSR restrictions and can secure higher loan limits based on business feasibility.

Critical Risks You Must Understand

While the advantages of registering as a property trader are clear, the risks are often underestimated. Most problems arise when these points are not fully understood in advance.

Comparative Taxation

In regulated areas, tax authorities may apply comparative taxation, choosing the higher tax between short-term capital gains tax and progressive income tax with surcharges.

VAT on Large Properties

For properties exceeding 85㎡, VAT at 10% may apply to the building portion, significantly reducing net profits if not properly calculated.

Health Insurance Premiums

Once business income is generated, former dependents may be reclassified as regional subscribers, leading to substantial monthly insurance premiums based on income and assets.

Who Should and Should Not Register

The key question is not whether a property trading business is good or bad, but whether it fits your investment style and personal situation.

Traders who engage in frequent short-term deals with high expenses often benefit from registration. However, one-time sellers or high-income earners may face greater overall costs.

As a general rule, if most factors place you in the “recommended” category, registration may be worth considering. Otherwise, caution is advised.

Practical Checklist for Beginners

Final Thoughts

A property trading business is not a universal tax solution. It is simply a tool that works well for some investors and poorly for others.

For those who trade frequently, understand their cost structure, and are aware of their income and insurance implications, it can be a powerful strategy.

For others, especially one-time sellers, the hidden costs may outweigh the benefits.