Korea's COFIX climbs a fourth month, pushing variable mortgage ceilings to 5.89%

Korea's COFIX benchmark for newly handled loans rose 0.13 percentage points in July to 3.18%, a fourth consecutive monthly increase since April ^[1]. From the 19th, KB Kookmin Bank moves its COFIX-linked variable mortgage range to 4.38-5.78% and Woori Bank lifts the ceiling on variable rates for newly handled loans to 5.89%, within a range of 4.69-5.89% ^[2][3]. For anyone holding property on floating-rate debt, the top of the band is now 2.71 points above the index it tracks ^[1].

The index level itself is not extreme. At 3.18% it is the highest in one year and seven months, and it remains 0.04 points below December 2024's 3.22% ^[4][2]. The other two variants also moved up: balance-based COFIX to 3.00% and new balance-based COFIX to 2.65% ^[5][6]. The 0.53-point gap between the newly handled and new balance-based series ^[3] is a useful measure of repricing still in the pipeline for borrowers whose loans reset off the slower index rather than off new origination.

The forward view is where the cash-flow arithmetic gets uncomfortable. A financial industry official quoted by en.sedaily.com said the possibility of the base rate rising to 3.75% early next year cannot be ruled out if the pace of increases quickens ^[7]. The same briefing expects both fixed and COFIX-linked rates to keep rising this year, and says investors with high borrowing levels urgently need to recalculate their interest costs ^[8]. That is not a forecast an operator can hedge with optimism; it is a debt service line item.

The usual release valve is selling, and that valve is being rebuilt. Democratic Party leader Kim Min-seok will hold his first high-level party-government meeting after taking office on the 23rd to discuss supplementing the government's real estate tax reform plan ^[9]. As drafted, the reform phases out the holding-period deduction of up to 40% for non-resident single-home owners, which raises the effective capital gains burden to the level of a tax increase for those holding homes worth 1.2 billion won or more ^[10]. Kim signaled opposition to that provision at the party convention, so the reform is seen as likely to be substantially revised, and lawmakers from Seoul districts are pressing for broader exceptions recognising actual residence ^[11]. Sellers therefore face a rate curve that is moving now against a tax rule that may not settle for weeks.

Supply policy is equally unsettled. Follow-up measures to the plan for more than 230,000 homes in the Seoul metropolitan area and steps to invigorate urban redevelopment are also on the agenda for the 23rd ^[12]. Seoul Mayor Oh Se-hoon opposed housing supply at Yongsan Park at a Cabinet meeting, proposing instead that restrictions on the transfer of union membership status, floor area ratios and rental housing quotas be eased ^[13], and named the Armed Forces Financial Management Corps site in Huam-dong and Itaewon-dong, a Ministry of Foreign Affairs parking lot and a Bank of Korea residential facility as alternative sites ^[14]. President Lee Jae-myung pushed back, saying, "The goal is to expand supply, but it must not raise the likelihood of a surge in home prices" ^[15].

Three things to watch: the August COFIX print, for whether the run extends to five months ^[1]; the output of the 23rd party-government meeting on the holding-period deduction, which determines the after-tax proceeds of any sale decided this quarter ^[9][10]; and whether the base rate speculation at 3.75% starts appearing in bank pricing rather than in commentary ^[7].