Side hustle 2026 in Korea, the first year's filing and checking dates in calendar order
2026-10-25
Search YouTube for side hustle 2026 and the top five videos together have more than six million views. The titles are about starting: five ideas, eight ideas, what works in your twenties.
What goes on the calendar after starting is not in those videos. For someone in Korea it is a registration deadline, November 30, the end of February and March 10 of the next year, late April, May, and then November again.
This post lines up the first year of a side income started in Korea in 2026 using the dates written on National Tax Service (NTS) and National Health Insurance Service (NHIS) pages. Tax rates by income type are in the side hustle taxes post, so here it is dates and order only.
1.One thing to settle before opening the calendar
The first box depends on whether the money is business income or other income. The NTS treats personal services provided continuously and repeatedly as business income for reporting, and one-off services as other income (NTS statement guide).
Assumption: the example is 500,000 won a month, 6 million won a year. Real amounts and expenses differ.
If the 6 million won is other income, 60% of it counts as expenses and the income amount is 2.4 million won (other income withholding). If it is business income, the income amount is what remains after actual expenses.
2.From the first day to the following May, in calendar order
Within 20 days of starting: business registration
Selling goods or providing a service on an ongoing basis starts with business registration. The NTS guide says to apply at the tax office before opening or within 20 days of the day business starts, and Hometax accepts the application online (NTS business registration).
Freelance work paid by a company with 3.3% withheld reaches the NTS without registration, and leads to the May filing the next year(NTS filing guide).
End of every month: the payer's deadline, not yours
The company or platform that paid the money files a simplified payment statement with the NTS by the end of the month after payment. Business income is monthly, and other income has been monthly since January 2024 payments (business income statement).
The person doing the side hustle has nothing to do this month.
November 30: a box that usually stays empty in year one
People with comprehensive income pay an interim income tax prepayment in November. For 2026 the estimate filing and payment deadline is Monday, November 30 (interim estimate guide).
The NTS excludes anyone who was not a business operator on December 31, 2025 and newly started in 2026. People with only wage or other income, and anyone whose amount is under 500,000 won, are excluded too (interim prepayment guide).
Starting in 2026 means the first November 30 passes by, and the question comes back from November 2027.
End of February and March 10 of the next year, then late April
Annual payment statements are due by the end of February for other income and by March 10 for business income. This too is the payer's duty (payment statement filing).
The earner checks on Hometax. MyNTS has a page listing statements filed about you for the last five years, and the Hometax manual says the current year's filings can be viewed after late April (Hometax manual).
Opening that page in late April and finding a line that does not match what was received leaves time to ask the payer before the May filing.
May 1 to 31: comprehensive income tax
Comprehensive income tax is filed and paid from May 1 to May 31 of the following year. If the deadline falls on a Saturday or holiday it moves to the next day, and May 31, 2027 is a Monday (filing deadline).
If the assumed 6 million won is other income, the income amount is 2.4 million won, under the 3 million won line for withheld other income, so the earner can choose between adding it to comprehensive income or letting the withheld tax end it (comprehensive and separate taxation).
Business income gives no choice. It is filed together with salary, and missing the deadline means no refund.
3.Health insurance moves a year later, in November
Employee members whose income outside salary passes 20 million won a year get a separate income-based premium, paid entirely by the member. Business and other income count at 100% of the income amount, wage and pension income at 50% (NHIS guide).
When it starts is this post's question. Article 41 of the Enforcement Decree of the National Health Insurance Act uses the previous year's income data for November and December premiums, and data from two years before for January through October (Enforcement Decree art. 41).
Side income earned in 2026 is filed in May 2027 and shows up in premiums from November 2027 through October 2028. The 2026 health insurance rate is 7.19% (Ministry of Health and Welfare release).
The assumed 6 million won is under 20 million, so no income-based premium arises. The month it shows up is a year away, but whether the line is crossed is decided by income inside 2026.
Regional members see the same November. The NHIS writes that the NTS hands over the previous year's income data every November (regional premium adjustment).
4.If the start date is October 25, 2026
These are the dates with the assumption that the side income starts on the day this post goes out.
- November 14: business registration deadline (20 days from the start)
- November 30, 2026: interim prepayment, not applicable as a new business
- Early 2027: the payer's statement deadlines, February 28 and March 10
- Late April 2027: check filed statements on Hometax MyNTS
- May 1 to 31, 2027: comprehensive income tax filing
- November 2027: 2026 income reaches health insurance premiums
Three lines
- Register within 20 days; the November 30 interim prepayment skips the first year; file from May 1 to 31 the next year
- Payment statements are the payer's duty; the earner checks them on Hometax MyNTS after late April
- Health insurance picks up the previous year's income from November, and only above 20 million won for employee members
Hiddenpick is a Windows program that keeps on its server the betting rules that pick owners do not make public, and runs them as they are on the PC of the person who received them through a referral code. It currently runs on Evolution live baccarat at Stake (stake.com). Income from a program left running follows the same calendar above, and what the program does is in the baccarat bot guide.
We are recruiting national pickster representatives, and those selected receive benefits worth $12,000, a one-year pass. Apply: https://hiddenpick.my/pickster
- 25,000+ real shoes collected and analysed since September 2026
- 90+ baccarat tables from the lobby on one screen · refreshed every 0.35s · seated 2 to 4 seconds after a click
- Stops by itself at your take-profit and stop-loss · tie several PCs into one team and stop on the total
- No browser extension · your money stays in your own Stake account · 12 languages