Stock Capital Gains Tax Basic Deduction 2,500,000 KRW, Practical Guide

TL;DR

• The stock capital gains tax basic deduction reduces taxable income at filing, and applying it requires accurately tallying annual gains and losses.
• Beginners should follow a sequence: check trading records, calculate annual gains and losses, keep tax documents, then file and pay. Verify figures and requirements with the relevant authority.

1. Core concept and required documents

The basic deduction applies on an annual basis, subtracting a fixed amount from capital gains to lower taxable income. The key point is the "annual net gain." Depending on holding period or trading method, the way you aggregate gains and losses can differ, so prepare broker trading records (buy/sell data by account), dividend and fee records. Confirm up-to-date rates and limits with your broker or the tax authority.

2. Step-by-step procedure

1) Download trading records: Obtain files of all accounts' buy and sell records by year. Use mobile or web trading history tools.
2) Calculate annual net gain: Aggregate gains and losses by the same security and reconcile losses and gains. Netting rules can be complex, so consult a tax professional or your broker if unsure about standard calculation methods.
3) Determine basic deduction applicability: Check whether annual net gain falls within the basic deduction range. Only the portion exceeding the basic deduction is taxable. Rules may change, so confirm current guidance.
4) File and pay: Verify the capital gains tax filing period and methods (e-filing, mail, etc.) and submit within deadlines. Required documents include trading records, supporting evidence, and ID copies.

3. Evidence and record retention tips

To avoid tax disputes, keep original or electronic trading records and supporting documents. Confirmation documents issued by counterparties or brokers are important. Records of partial sales or transfers can affect gain calculations, so document them in detail.

4. Beginner cautions and tax-saving notes

• If gains and losses are spread across multiple accounts or brokers, aggregation becomes harder. Create an annual summary to manage them centrally.
• Netting rules between loss years and gain years may be subject to separate provisions. Confirm specifics with the tax authority or your broker.
• Short-term or large-volume trading may affect reporting obligations or taxation methods, so check rules according to your trading style.

This article is for informational purposes and is not investment advice.