Short answer: that free signup bonus can cost you more than it pays out. A friend took a ₩200,000 cash bonus on a 3-year internet bundle, then paid a ₩217,107 penalty to cancel after 12 months — a net loss of ₩17,107, on advice I gave her myself.
That’s not a hypothetical. My friend — newly arrived on a one-year teaching contract, her ARC (Alien Registration Card, 외국인등록증, oegugin-deungnok-jeung, literally “foreigner registration card”) still warm from the immigration office — asked which internet plan to get. I told her it didn’t matter, just pick whatever the installer was pushing. It mattered. Here’s the contract math I should have walked her through first, built off a real broker listing and her actual bill.
Why Every Internet Plan Here Comes With a Three-Year Catch
Every carrier — SK Broadband, KT, and LG U+ — sells home internet on three contract lengths: 12, 24, or 36 months. On paper they look interchangeable. In practice, the cash on the table is not evenly split. The biggest cash signup bonuses (사은품, sa-eun-pum, literally “thank-you gift”) are attached almost exclusively to 36-month bundles that pair internet with a TV package. A 24-month bundle typically gets little to none, same as a plain 12-month contract — the meaningful cash bonus is reserved almost entirely for the 36-month bundle.
Getting connected takes less effort than the contract math suggests. You need a passport or ARC, proof you live somewhere — a rental contract works — and a Korean phone number, and installation is usually done within one to three days of applying. There’s a one-time setup fee, typically ₩30,000 to ₩70,000, that most signup promotions waive outright. None of that part is the trap — the commitment behind the good version of the deal is.
Three years is a long time to guess right.
The ARC Rule Nobody Mentions Before You Sign
Carriers check something most signup guides skip entirely: whether your ARC will still be valid when the contract is supposed to end. Sign a 36-month bundle, and the carrier wants an ARC with close to three years of runway on it, or clear proof a renewal is already in motion — an ARC with under roughly 12 months remaining is routinely turned down for a multi-year plan. My friend’s ARC cleared that bar easily; she’d just been issued a fresh one-year E-2 visa with an option to extend, so nothing about the paperwork raised a flag.
The problem was never her ARC’s validity. It was that I told her to treat a 36-month commitment like it was a 12-month one, because in my head “sign the internet contract” and “plan your next three years in Korea” were unrelated decisions. They are not. (I wrote separately about a coworker fighting the newer Mobile Residence Card system for an hour — different document, same lesson: nothing about Korean paperwork forgives a wrong guess.)
Where the Cash Bonus Actually Comes From
None of that ₩200,000 shows up if you go straight to SKT.com, KT.com, or LG U+’s own site — you’ll see standard rate plans, not a single mention of a cash bonus. The money moves through a separate channel: comparison sites and local agencies that carriers pay a commission to for bringing in signups, who pass a chunk of that back to the customer as the bonus, either a straight bank transfer within a week or two of installation, or a waived first month’s bill.
Nobody puts that on a billboard.
The Regulator’s Math: A ₩470,000 Cap and a 15% Rule
There is a ceiling on all of this, and it comes from Korea’s broadcast and telecom regulator, the KCC. The legal cap on a signup gift for an internet-plus-TV bundle sits at roughly ₩470,000 to ₩480,000, combining cash and any gift certificates thrown in. What changed more recently is how that ceiling gets enforced. It used to be a flat number everyone tried to sit just under. Now it works as a non-discrimination rule: a carrier is in violation if any single payout runs more than about 15% above its own recent average payout, on the theory that wild swings between customers — one person getting ₩470,000, the next getting ₩50,000 for an identical plan — are the real abuse, not the total amount. “The guy down the street got double what I did” is now a specific, checkable complaint, not just a feeling.
The Real Numbers: A ₩200,000 Bonus and a ₩217,107 Exit Fee
Here’s the listing my friend actually signed, pulled from a broker site rather than any carrier’s own page: LG U+, 100Mbps, a 36-month bundle at ₩22,000 a month, with a ₩200,000 cash bonus paid out after installation. She left at month 12, when her teaching contract wasn’t renewed. The termination penalty (위약금, wiyakgeum, literally “penalty money”) on the way out was ₩217,107.
Weighed against just the bonus, that’s a straightforward loss: ₩217,107 minus the ₩200,000 she’d already been paid comes to a net loss of ₩17,107 — the “free” signup gift, once you account for leaving early, cost her money instead of saving her any.
That’s the number that stings.
But it’s not the number that actually matters if you’re asking whether taking the bonus was worth it in the first place. I ran the full 12 months both ways to check. On the bonus route: ₩22,000 × 12 months in fees is ₩264,000, minus the ₩200,000 bonus, plus the ₩217,107 exit penalty, comes to ₩281,107 total for a year of internet. The alternative — skipping the bonus entirely and signing the plain 12-month contract at ₩34,100 a month, the rate a bonus-free plan runs at the same speed — comes to ₩409,200 for the same year.
| Path | Monthly fee × 12 | Bonus / penalty | Total for 12 months |
|---|---|---|---|
| 36-month bundle, bonus taken, canceled at month 12 | ₩264,000 | −₩200,000 bonus, +₩217,107 penalty | ₩281,107 |
| Plain 12-month contract, no bonus, no early exit | ₩409,200 | none | ₩409,200 |
So my friend was right to be annoyed at the ₩217,107 line item, and I was wrong to wave the whole decision off as trivial — but she still came out roughly ₩128,000 ahead of where she’d have landed on a plain 12-month plan from day one, even after eating the penalty. That’s the part neither the abstract guides nor the angry moment at the carrier counter capture: a bonus that loses money in isolation can still beat the no-bonus alternative, because the discounted monthly rate on longer bundles does more work than the penalty undoes. The break-even point isn’t really about ₩217,107 versus ₩200,000. It’s about whether the monthly-rate gap between your contract length and the shortest alternative is wide enough to absorb whatever penalty you’ll owe walking out.
How to Time a Cancellation So You Do Not Lose Money
Two more numbers decide whether leaving early costs you the bonus itself, not just a termination fee. Sign directly at a carrier’s own store, and you’re on the hook to return the bonus if you cancel within one year. Sign through a broker or comparison-site agency — how almost everyone actually gets the bonus — and that clawback window is shorter, just nine months. My friend signed through a broker and canceled at month 12, three months past that nine-month line, so she kept the ₩200,000 outright. The ₩217,107 she paid was purely the standard termination fee for breaking a 36-month service commitment early, unrelated to the bonus itself.
Since a 2023 reform, that termination fee doesn’t sit at one flat number either — it follows a curve that rises toward a peak around month 18 of the contract, then tapers back down toward ₩0 as you approach the natural 36-month end date. Cancel at month 12, like my friend did, and you’re still climbing that curve; wait until month 18 and you’d likely pay more, not less. Cancel in the back half of the contract — month 28, month 30, later — and the fee has largely worked itself down already.
Put the two rules together and the actual danger zone isn’t the mid-contract peak everyone warns about — it’s the first nine months, full stop. Cancel there and you owe back the entire bonus on top of whatever the fee curve says, the one combination that reliably loses money no matter what. If there’s any real chance your ARC, visa, or job here won’t outlast the contract, the plain 12-month plan at the higher monthly rate is the boring, correct answer.
Frequently Asked Questions
Does my ARC need to already cover the full contract length before I sign?
Close to it. Carriers expect an ARC whose remaining validity covers roughly the plan’s length — for a 36-month bundle, close to three years left, or proof a renewal is already in motion. Under about 12 months remaining is commonly turned down for a multi-year contract.
Why can’t I just find the cash bonus on the carrier’s own website?
Because it isn’t there. SKT, KT, and LG U+ publish standard rate plans on their own sites, not signup bonuses. The money flows through comparison sites and local agencies earning a commission for the signup, paid to you as a bank transfer after installation or a waived first-month bill.
What happens if I cancel before the clawback window ends?
You owe the bonus back, on top of the standard termination fee. That window is one year through a carrier’s own store, or nine months through a broker or comparison-site agency — which covers most cash-bonus signups. Cancel inside it and you’re paying twice.
Is the ₩470,000 cap a guarantee I’ll get close to that amount?
No — it’s a ceiling, not a target. The KCC bars a carrier from paying any customer more than about 15% above its own recent average payout, so the real offer depends on current promotions, not the legal maximum. ₩200,000–₩250,000 is realistic for a solid 36-month bundle; ₩470,000 is a best case, not typical.
What I Would Tell Her Now
If my friend asked me the same question today, I wouldn’t tell her which carrier to pick. I’d ask one thing first: how sure are you about being here in twelve months? If the honest answer is “not sure,” the plain 12-month contract at ₩34,100 is the right call even though the number looks worse on day one — no bonus to claw back, no fee curve to climb. If it’s “pretty sure,” the 36-month bundle is genuinely the better deal, bonus and all, and the ₩217,107 my friend paid says more about bad timing than a bad contract. I got the advice wrong the first time because I treated it like a phone-plan-sized decision. It’s a three-year bet with your ARC as collateral — and the signup bonus turns out to be close to the least important number in it.