CoffeeNetwork (New York) - Indonesia’s leading coffee island, Sumatra, just delivered one of the most decisive supply signals of the 2025/26 coffee year. Government trade data show December robusta exports at 541,672 bags, up 52.06% year‑over‑year, pushing cumulative April–December shipments to 5,217,056 bags, up 80.56% versus the same span last year. Taken together with upgraded national crop forecasts and steady domestic use, the numbers point to a larger Indonesian exportable surplus in 1H–2H 2026, with direct implications for London futures, differentials, and buyers’ coverage strategies.
The 541,672‑bag December total from Sumatra is not a statistical blip. It caps nine months (Apr–Dec) of accelerated shipments totaling 5.217 million bags, a pace broadly consistent with the USDA FAS upgrade of Indonesia’s 2025/26 crop to ~12.5–12.6 million bags, roughly 85% robusta. Put simply: supply is back after weather‑curbed output in 2023/24 and a slower 2024/25.
Complementary reporting across the trade press reaches the same conclusion. The USDA FAS Semi‑Annual (Dec 2, 2025) singled out southern Sumatra (Lampung, Bengkulu, South Sumatra) for faster‑than‑expected robusta recovery on improved rainfall, inputs, and pruning. Daily Coffee News’ Jan 6, 2026 wrap cites 12.5M total with ~11M robusta and green exports at 7.8M, reflecting both agronomic improvement and the tailwind of a weaker rupiah.
Indonesia’s 2025/26 balance is still robusta‑heavy (85% of output), with domestic consumption near 4.8–4.81M bags. That mix, together with the December shipping surge, implies more robusta available to export (particularly Lampung/Bengkulu FAQ‑type grades) and steady demand for imports of other origins to support local roasters’ arabica or specific blend needs.
The USDA FAS narrative also notes Sumatra accounts for 70–75% of Indonesia’s production, with southern Sumatra dominating robusta and northern Sumatra supplying most arabica—geography that explains why Sumatra’s monthly shipping pulse is an outsized barometer for the national picture.
On the board, robusta has softened in recent sessions as the market prices in stronger Asian shipments; at the same time, arabica has eased amid improved Brazilian rains that favor 2026 development. While multiple factors move futures, the Sumatra print adds hard evidence to the “more robusta coming” thesis, which can pressure the London curve and origin differentials (e.g., Lampung FAQ vs Vietnam 2/3). Near‑term, look for tighter diffs where Indonesian flows accelerate and buyer optionality widens.
Parallel origin commentary underscores this interplay: with Brazil’s Minas Gerais receiving 117% of normal rainfall into late January, arabica price relief has persisted relative to 2025 highs; robusta futures, meanwhile, have been more sensitive to Vietnam and Indonesia shipping rhythms. The Sumatra surge effectively validates the bearish‑leaning supply narrative for robusta into Q1–Q2.
A bigger crop is not automatically a consistent one. USDA FAS cautions that heavy monthly rains across parts of southern Sumatra (Nov–Jan) can elevate humidity and drying risks, especially during peak flow. For buyers, that raises the odds of wider moisture and water‑activity dispersion, mixed screen/defect profiles, and lot‑to‑lot cup variability if post‑harvest and sorting standards vary. Mitigation playbook: tight moisture/aw specs, representative sampling, lot separation, and pre‑shipment re‑checks before loading.
Logistics are another lever. A weaker rupiah has supported export competitiveness, but congestion can still flare when shipment windows overlap across Lampung/Bengkulu; coupling fixed diffs with lead‑time buffers and container optionality (e.g., alternate feeder ports) is prudent until throughput normalizes.
Indonesia’s domestic consumption is projected around 4.8–4.81M bags in 2025/26—essentially steady growth—so the bulk of the 2025/26 incremental crop will channel to export. That dynamic, combined with Sumatra’s Apr–Dec +80.56% shipping outturn, argues for better availability for international buyers through mid‑year, with U.S. and EU taking meaningful shares (EU particularly for robusta). It will be important to keep a close eye on tactical shifts if tariff regimes or EU Deforestation Regulation (EUDR) enforcement timelines alter documentation requirements later in the year.
Alexis Rubinstein
