Korea Phone Deal Calculator (25% plan discount vs device subsidy vs unlocked phone)

How it works

Total cost over the contract = phone amount you finance + instalment fee + plan fees. Device subsidy: you finance price − subsidy − store support and pay the full plan fee. Plan discount (선택약정): you finance the full price and pay the plan fee × (1 − discount). Unlocked + budget plan: unlocked price (plus any instalment fee) + budget plan fee × months. Instalment fees use equal monthly payments: payment = A × i ÷ (1 − (1 + i)⁻ⁿ), i = rate ÷ 12. Early-termination charges, plan changes in the first months and add-on services are not included.

⚠ Estimates for information only — not financial advice.

FAQ

When is the 25% plan discount better than the subsidy?

When plan fee × 25% × months is larger than the subsidy plus store support. With an 85,000-won plan over 24 months the discount is worth 510,000 won, so a subsidy above that wins.

Can I get the 25% discount on an unlocked phone?

Yes — an unlocked phone used on a carrier plan can sign up for the selective-agreement discount. Enter the unlocked price as the carrier phone price and set the subsidy to 0 to model it.

Checked 11 Nov 2026. Korea: the 25% selective-agreement discount (선택약정할인) is a discount on the monthly plan fee chosen instead of the device subsidy; it was kept in the Telecommunications Business Act when the Mobile Device Distribution Improvement Act (단말기유통법) was repealed on 22 July 2025, which also removed the cap on extra store support (Ministry of Science and ICT announcements, July 2025). Subsidies and plan prices: carriers’ own published notices — enter the ones valid on the day you buy.