A logistics manager in Medan told me in March that her company’s truck-turn time between Medan and Pekanbaru had dropped by close to a third in the past eighteen months. That’s a meaningful number for a route that historically defined the cost-and-time profile of moving freight across northern Sumatra, and it’s the most concrete example I’ve heard of the Trans-Sumatra Toll Road project finally delivering operational benefits at scale. The story of Sumatra’s logistics in mid-2026 is, in large part, the story of this road and the port upgrades that accompany it.

Indonesia’s logistics costs have historically run somewhere between 14% and 24% of GDP depending on whose methodology you accept — well above the regional benchmark and well above what a country of Indonesia’s economic complexity should be paying. Sumatra has been a disproportionate part of that drag, both because the island is large and elongated, and because its primary cities sit hundreds of kilometres apart along an axis that the existing road network served badly.

The Trans-Sumatra Toll Road, finally

The Jalan Tol Trans-Sumatra (JTTS) project has been officially under construction since 2014, with target completion dates that have shifted multiple times. As of mid-2026, the operational sections cover most of the southern portion (Bakauheni–Palembang and the Palembang area extensions), substantial parts of the central section (Pekanbaru and the Riau-Sumatra Barat connectors), and the Medan area in the north. The full backbone connecting Bakauheni at the southern tip to Banda Aceh at the northern is still incomplete; certain sections remain under construction or in tender for the next phase.

What’s already operational has changed unit economics for specific corridors. The Bakauheni–Palembang section reliably runs in 4–5 hours where the parallel non-toll route still takes 9–11. For palm oil, rubber, paper, and the industrial cargo that moves through Lampung and South Sumatra, the savings on diesel, driver wages, and inventory in transit are now material to operating margins.

The northern Medan corridor, including the routes connecting to Belawan port and toward Pekanbaru, is where the manager I spoke with was getting her improvements. The Pekanbaru–Dumai section in particular has shifted some palm-oil logistics calculations meaningfully, given Dumai’s role as one of Indonesia’s larger crude-palm-oil export ports.

Port modernisation, with caveats

The port story is uneven. Belawan in North Sumatra has had substantial investment over the past several years and now handles container volumes more efficiently than it did, though dwell times remain higher than at Tanjung Priok. Kuala Tanjung, the deep-water port intended to compete with Singaporean transhipment for Sumatran origin and destination cargo, has a more mixed track record — the throughput hasn’t quite met the projections used to justify the original investment, and a meaningful share of Sumatran international cargo still routes via Singapore.

Panjang in Lampung, Boom Baru in Palembang, and Teluk Bayur in Padang have all seen incremental upgrades. The constraint at most of them is no longer dock-side capacity but the inland connectivity that determines how quickly cargo actually clears the port and reaches its destination. This is where the Trans-Sumatra toll road and the parallel rail upgrades start to combine, at least in principle.

Bank Indonesia’s regional economic reports have tracked these dynamics in some detail; the Bank Indonesia regional economic publications for the Sumatra regions are a useful, if dense, source for the actual freight-volume data underneath the broader logistics narrative.

E-commerce last-mile, separately

The B2C and e-commerce last-mile picture in Sumatra is a different story than the bulk-freight one. The major Indonesian couriers — JNE, J&T, SiCepat, Anteraja, plus Pos Indonesia in its modernised form — have all expanded coverage substantially in Sumatra’s secondary cities over the past three years. Same-day or next-day delivery in Medan, Palembang, Pekanbaru, and Padang is now table stakes; T+2 or T+3 to district capitals like Tanjungpinang or Lubuklinggau is normal where it would have been T+5 to T+7 a few years ago.

The constraint that remains is the truly remote areas. Western Sumatra’s mountainous terrain, the inland districts of Riau and Jambi, and the islands of the Mentawai chain still see delivery economics that don’t pencil out for private couriers and that remain dependent on Pos Indonesia and KSP service. The cross-subsidy structure that supports remote delivery is one of the genuinely interesting policy questions for the next phase of Indonesian e-commerce regulation.

The motorcycle-courier ecosystem that defines Jakarta’s last-mile is present in Sumatran cities but at lower density. Gojek and Grab both operate in major Sumatran cities; their volume mix is more biased toward food and on-demand than toward parcel delivery, with implications for the unit economics of e-commerce drop-offs.

What’s still missing

A few things that the next three to five years will likely need to address.

Inland container-handling capacity remains thin. The Trans-Sumatra toll road accelerates road movement, but the staging yards, the cross-docks, and the fulfilment-centre layer that would let an e-commerce or industrial operator efficiently distribute across Sumatra from a regional hub are still mostly absent outside Medan and Palembang. This is genuinely starting to change — there’s been credible greenfield investment in distribution-centre capacity in 2025–2026 — but the gap is still real.

Cold chain in Sumatra is meaningfully behind Java. The fish exports from Sibolga, the dairy operations in the highlands, and the increasingly export-oriented horticulture from West Sumatra all need cold-chain links that don’t fully exist or that exist with reliability problems. Some of the most interesting logistics-tech startups in Indonesia are actually addressing the Sumatran cold-chain gap rather than the more obvious Jakarta opportunities.

The rail-freight connection that was meant to complement the toll road has progressed slowly. The South Sumatra coal-haulage rail is operationally significant but the broader passenger-and-freight rail upgrades have lagged. Whether they will catch up is one of the open questions of the current infrastructure planning cycle.

The picture as of mid-2026 is, on balance, one of substantial progress with significant unevenness. Sumatra’s logistics costs have come down, but they haven’t come down uniformly, and the operators who win in the next phase will be the ones who design their networks around the corridors that are now genuinely fast — and accept that the rest of the island is still going to be slow for a while longer.