Is money earned selling courses on Inflearn or Class101 business income or other income?
If you make and sell courses on a continuous, repeated basis, it is classified as business income and subject to comprehensive income tax filing every May, and if your YouTube AdSense revenue is also business income, it is combined into that same filing rather than reported separately. You should not report only the settled amount after platform fees as revenue: in principle, you record the full sale price as revenue and deduct the platform fee separately as a necessary expense, which is essential to avoid an amended filing and penalties.
Income Structure Features for Online Course Creators
Key Necessary Expense Items
Tax Advantages for Online Course Creators
Design Tax Savings by Consolidating Income Across Platforms
Managing income from Inflearn, Class101, YouTube, and other channels as a single business income stream lets you systematically apply expense ratios and tax-saving strategies like the Nolan Umbrella Fund.
Spread Equipment Investment Through Depreciation
Filming equipment like cameras and lighting over 1 million KRW should be depreciated over time, while consumable equipment of 1 million KRW or less can be expensed in full immediately upon purchase.
Consider Zero-Rate VAT for Overseas Platform Sales
Sales through overseas course platforms like Udemy may qualify for the zero VAT rate if recognized as a foreign-currency-earning service.
The Most Common Mistake in the Field
The most common mistakes are reporting only the settled amount after platform fees as revenue, or missing part of the income from multiple platforms. In principle, you must record the full sale price as revenue and deduct the platform fee as an expense, and since this is cross-checked against platform payment records, omissions can lead to an amended filing and penalties.