Upbit and Bithumb lose half their revenue, and the fee-only model shows its cost base

Dunamu, the operator of Upbit, told South Korea's Financial Supervisory Service that consolidated revenue for the six months to June 2026 was 408.1 billion won, roughly $289 million, down 49.1 percent year over year ^[1][3]. Bithumb filed the same shape of number: 168.8 billion won, about $119 million, down 48.7 percent ^[2]. When two competitors lose half their top line in the same six months, that is not a company story.

The product is the transaction fee. Korean venues take the vast majority of income from fees on spot and other trades, so when volume falls, fee revenue falls almost in direct proportion ^[5]. Combined volume across the five major won-based exchanges was about $367 billion in the first half, down more than 54 percent from the same period of 2025 ^[4]. Revenue declines of roughly 49 percent landed about five percentage points inside that ^[23], which is close to pure pass-through.

What did not pass through proportionally was cost. Dunamu's operating profit fell by nearly 80 percent ^[6], about 1.6 times the rate of its revenue decline ^[19]. Bithumb's fell more than 83 percent, roughly 1.7 times its own revenue decline ^[7][20], and it posted a net loss above 108 billion won, near $70 million ^[7], equal to about 64 percent of the half's revenue ^[21]. Part of that loss came from non-operating items, including valuation adjustments on crypto holdings and provisions ^[8]. That is its own tell: an exchange carrying token inventory is also long the asset whose volatility it sells access to.

The base being compared against was large. Dunamu's implied prior-year first half was about 801.8 billion won ^[17] and Bithumb's about 329.0 billion won ^[18], against combined 2026 revenue of 576.9 billion won ^[16]. Roughly 554 billion won of half-year revenue disappeared in twelve months ^[24]. Against the industry's $367 billion of volume, the two firms' approximately $408 million of revenue implies a blended take of about 11 basis points, though the volume figure spans all five venues rather than only these two ^[22].

The causes are ordinary. Lower price volatility in bitcoin and alternative tokens discouraged the retail investors who dominate the Korean market ^[11], while sustained high US interest rates pulled capital toward equities, particularly artificial intelligence and semiconductor names ^[12]. Customer deposit balances fell at both exchanges ^[9]. Liquidity concentrated on the largest venue: Upbit added to its already dominant share while Bithumb's slipped ^[10], so the smaller firm absorbed the cycle and share loss at once.

Both have tightened operating expenses and are trying promotional and product initiatives to stimulate engagement ^[13]. Neither response changes the input. The source's own framing is that structural dependence on trading fees keeps performance highly sensitive to market conditions and risk appetite ^[14], and that the half underscores the cyclical nature of the model and the value of diversified revenue ^[26]. The cycle is the weather; the fee-only mix and the unflexed cost base are the building.

Watch the next quarterly disclosures, which regulators and market participants will read for stabilisation or further contraction ^[25]. Deposit balances are the earliest read on whether volume returns ^[9]. Watch whether the Upbit-Bithumb share gap keeps widening ^[10], and whether either firm books revenue that is not a trading fee. On the source's account, a volume recovery depends on macro improvement, rate easing, or renewed price momentum ^[15], none of which either company controls.