HomeTax Guide for Foreigners in Korea 2026: 10 Tips for Filing Taxes Yourself
Korea’s HomeTax (hometax.go.kr) is the online tax filing system operated by the National Tax Service. Filing your comprehensive income tax (jonghap sodeukhse) yourself through HomeTax saves 100,000 to 300,000 KRW in accountant fees. You can log in with simplified authentication (Kakao, Naver, PASS) in 30 seconds, and the pre-filled return (moduchae-um) service lets eligible filers complete their return in about 5 minutes. Refunds typically arrive within 2-4 weeks.
Here are 10 practical tips for navigating HomeTax in 2026.
Tip 1: Log In Using Simplified Authentication
The biggest barrier to HomeTax used to be the certificate system. In 2026, that barrier is gone.
Simplified authentication options:
- Kakao Talk authentication
- Naver authentication
- PASS authentication (mobile carrier)
- Toss authentication
- KB Kookmin authentication
Kakao Talk is the easiest. On the HomeTax login screen, select “simplified authentication” (ganpyeon injeung), choose Kakao Talk, and confirm the notification on your phone. Done in 30 seconds.
Tip for foreigners: Make sure your Korean phone number is linked to whichever authentication service you choose. If you use Kakao Talk daily, that is the most convenient option.
Tip 2: Check If You Qualify for Pre-Filled Filing
The easiest way to file is through the pre-filled return (moduchae-um singo).
What it does:
The National Tax Service automatically calculates your tax based on income and deduction data it has already collected. You just review the numbers and click submit.
Who qualifies:
- Workers with a single income source
- Simple freelance income (3.3% withholding)
- Pension or other income only
- Anyone who received a moduchae-um notification from the NTS
How to check:
- Log into HomeTax
- Click “Comprehensive Income Tax Filing” (jonghap sodeukhse singo)
- If the “moduchae-um” option is available, you are eligible
If you qualify, filing takes about 5 minutes. However, if you have additional deductions the NTS missed, you might save more by filing manually.
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Tip 3: Choose the Right Filing Type
If you do not qualify for pre-filled filing, you need to select your filing type.
Filing types explained:
- Simple expense rate (dansun gyeongbiryul): For income below the threshold per business type. No bookkeeping required.
- Standard expense rate (gijun gyeongbiryul): For income above the threshold. Major expense receipts needed.
- Simple bookkeeping (ganpyeon jangbu): You keep basic records and claim actual expenses.
- Double-entry bookkeeping (boksik buki): Professional accounting required. Consider hiring a tax accountant.
How to find your type: After logging in, click “Filing Assistance Service” (singo dowoom seobiseu). It shows your income amount, applicable expense rate, and recommended filing type.
Tip 4: Use the Automatic Income Import
One of HomeTax’s most useful features is automatic income data retrieval.
Automatically imported data includes:
- Employment income (withholding receipts)
- Freelance income (3.3% withholding records)
- Interest and dividend income
- Pension income
- Other income (lecture fees, manuscript fees)
On the filing screen, click “Import Income” (sodeuk bulleo-ogi) and all your income sources appear. Verify that nothing is missing. If you have unreported income, add it manually to avoid penalties later.
Tip 5: Claim All Available Deductions
Deductions reduce your taxable income, and HomeTax auto-populates most of them.
Automatically available deductions:
- National Pension and health insurance premiums
- Credit and debit card spending records
- Cash receipt (hyeongeum yeongsujeung) usage
- Medical expenses
- Education expenses
- Donations
- Housing-related deductions
Deductions you may need to add manually:
- Monthly rent tax credit (requires lease contract + transfer records)
- Certain insurance premiums not auto-reported
- Business expenses when filing with bookkeeping
Key difference for foreigners: The year-end settlement (yeongmal jungsan) data from January is different from what appears during May’s comprehensive income tax filing. If you have both employment and freelance income, do not simply reuse your year-end settlement data.
Tip 6: Register Your Business Credit Card
If you have any business income, registering your credit card as a business card on HomeTax is essential.
How to register:
- HomeTax > “Inquiry/Issuance” > “Business Credit Card” > “Card Registration”
- Enter your credit card number
- Registration complete
Benefits:
- Business spending is automatically tallied
- VAT filing: input tax credits auto-calculated
- Income tax filing: business expenses auto-reflected
- Provides evidence during tax audits
Best practice: Keep separate cards for business and personal use. Register only your business cards on HomeTax.
Tip 7: Preview Your Return Before Submitting
Never submit without reviewing first.
Preview checklist:
- Total income matches your records
- All deductions are included
- Tax bracket is correct
- Pre-paid taxes (withholding) match your receipts
- Final amount (payment or refund) looks reasonable
If the tax due seems higher than expected, go back and check for missed deductions. National Pension, health insurance, and small business mutual aid (noran usan gongje) are commonly overlooked.
Tip 8: Use Installment Payment for Large Tax Bills
If your tax bill is large, you can split the payment.
Installment conditions:
- Tax due exceeds 10 million KRW
- First portion (up to 10 million KRW): due by filing deadline (May 31)
- Remaining amount: due within 2 months (by July 31)
No interest is charged on the second installment. However, missing the deadline triggers penalty charges.
Credit card payment is also available on HomeTax. Fees apply (0.8% for credit cards, 0.5% for debit cards), but combined with card installment plans, it can serve as an additional payment splitting tool.
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Tip 9: File Late Rather Than Not At All
Missed the May 31 deadline? File as soon as possible.
Late filing penalty reductions:
- Filed within 1 month after deadline: 50% penalty reduction
- Filed within 3 months: 30% reduction
- Filed within 6 months: 20% reduction
The sooner you file, the less you pay in penalties. HomeTax has a dedicated “late filing” (gihan hu singo) menu.
Tip 10: Save Your Filing Records
After filing, your work is not done.
Post-filing tasks:
- Save the receipt as PDF
- Print your return from “Filing History” (singo naeyeok johoe)
- Verify tax payment and save the payment confirmation
- Double-check your refund bank account is correct
Keep at least 5 years of filing records. They are needed for tax audits or amended returns. HomeTax stores your history digitally, but having your own copies is safer.
Common HomeTax Errors and Solutions
“Please install security software” error:
- Use the latest version of Chrome
- Disable popup blockers
- Reinstall the security module
“Session expired” error:
- HomeTax logs you out after 30 minutes of inactivity
- Save your work frequently using the temporary save function
- Prepare all documents before starting to minimize idle time
“Income data not found” error:
- The income payer may not have submitted their payment statement yet
- Try again after March
- If still missing, enter income manually
Best timing: HomeTax gets extremely slow during the last week of May. File in early to mid-May for a smooth experience. Early morning hours (1-6 AM) have the fastest load times.
Mobile vs Desktop: Which to Use
SonTax (mobile app) works well for:
- Pre-filled return filers
- Simple income structures
- Quick tax lookups and payments
- Cash receipt issuance
HomeTax (desktop) is better for:
- Multiple income sources
- Standard expense rate or bookkeeping-based filing
- Many deduction items
- Complex calculations
The most efficient approach is using SonTax for everyday lookups and the desktop version for actual filing.
Wrapping Up
HomeTax looks intimidating at first, but knowing these 10 tips makes it manageable.
The key steps: log in with simplified authentication, check if pre-filled filing is available, import your income and deductions automatically, preview everything before submitting, and save your records.
Filing yourself saves 100,000 to 300,000 KRW in accountant fees and gives you a much better understanding of your own tax situation.
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Can foreigners use HomeTax in Korea?
Yes. Foreigners with an ARC (Alien Registration Card) can register and use HomeTax. The interface is primarily in Korean, but you can use browser translation tools. Login is available through simplified authentication (Kakao, Naver, PASS) or a public certificate. Some basic functions are available in English through the National Tax Service English website.
What is the 'moduchae-um' (pre-filled) tax return?
Moduchae-um is a service where the National Tax Service pre-calculates your tax based on collected income and deduction data. If you are eligible, you simply review the amounts and submit. It takes about 5 minutes and is available for simple income structures like single-source employment or basic freelance income.
When do I get my tax refund after filing on HomeTax?
Tax refunds typically arrive 2-4 weeks after filing. If you file in May (the standard period), expect the refund by late June or early July. Late filings may take 2-3 months. The refund goes directly to the bank account you register during filing.
Do I need a tax accountant or can I file myself on HomeTax?
For simple income structures (single employer, basic freelance work), HomeTax's guided filing is sufficient and saves you 100,000-300,000 KRW in accountant fees. If you have complex income from multiple sources, real estate, or significant business expenses, a tax accountant is recommended.
