What percentage of Russian seaborne crude oil export loading capacity will be offline at end of June 2026 due to Ukrainian strikes (vs the H2 2025 baseline)?

TL;DR

Use 24% as the central estimate for the resolved value, with a mean of 23% and an 80% range of 9% to 32%. The March 40% outage has not persisted: by mid-June, Russian seaborne crude exports were near a 2026 high at 3.83 mb/d and western-port loadings were above the early-June plan. The resolution is most likely to use the fallback export-volume formula, which prints a mid-20s result even if the true physical loading capacity still offline is closer to single digits.

Context

Ukraine did cause a real shock in late March 2026. Reuters calculated that about 2.0 mb/d, or 40%, of Russia's oil export capacity was offline after attacks and suspensions at Primorsk, Ust-Luga and Novorossiysk; Novorossiysk was described as having about 700 kb/d of capacity in that report (Reuters via The Moscow Times, 25 Mar 2026).

By 21 June 2026, the flow evidence points to repair and rerouting rather than a standing March-scale crude-loading outage. Bloomberg-derived reporting put Russian seaborne crude exports at 3.64 mb/d in the four weeks to 31 May and said Baltic and Black Sea export terminals had largely resumed normal operations (Bloomberg via The Moscow Times, 2 Jun 2026); a later Bloomberg summary put the four-week rate at 3.83 mb/d through 14 June (Kommersant/Bloomberg, 17 Jun 2026).

Evidence

The historical backbone is that actual Russian seaborne crude exports normally run far below the 5.0 mb/d capacity denominator. That matters because the fallback resolution is $R=\max(0,(1-E_J/5.0)\times100)$, where $E_J$ is June 2026 average seaborne crude exports in mb/d. The first eight rows below are the full public IEA/Kpler/Argus May-vintage history in that report; the last three rows are the public Bloomberg checkpoints that frame the June window.

KSE's terminal-level reconstruction explains why March looked so bad. Using Kpler data accessed on 7 April 2026, KSE put 2025 port groups at 1.26 mb/d for Primorsk, 1.15 mb/d for Ust-Luga, 0.97 mb/d for Novorossiysk, 1.00 mb/d for Nakhodka/Far East, and 0.30 mb/d for Murmansk; that gives a practical 4.68 mb/d observed-flow backbone for the main seaborne export nodes (KSE Institute, 9 Apr 2026). In the same KSE data, Ust-Luga crude fell from 725 kb/d in the week of 16-22 March to 101 kb/d and 155 kb/d in the next two weeks, while Primorsk crude held at 780 kb/d and then 848 kb/d even as products were hit harder (KSE Institute, 9 Apr 2026).

The strongest June evidence is against a large continuing crude-loading outage. Reuters reported that May exports from Primorsk, Ust-Luga and Novorossiysk rose to 2.5 mb/d from 2.2 mb/d in April, the highest level for those western ports since September 2025, despite ongoing attacks on Novorossiysk and Transneft pipelines (Reuters via MarketScreener, 2 Jun 2026). Reuters then reported on 17 June that those same three western outlets averaged about 2.3 mb/d in the first half of June, compared with an earlier 1.7 mb/d preliminary full-month plan, because refinery outages left more crude to export (Reuters via Baird Maritime, 17 Jun 2026). The 3.83 mb/d Bloomberg four-week total through 14 June maps mechanically to 23.4% under the fallback formula (Kommersant/Bloomberg, 17 Jun 2026).

The contrary signal is that Ukraine kept hitting energy infrastructure during June. Reuters reported on 8 June that June loadings from Primorsk, Ust-Luga and Novorossiysk could fall to 1.7 mb/d from 2.5 mb/d in May as Russia tried to raise refinery runs and as output weakened (Reuters via Kitco, 8 Jun 2026). A drone strike caused a fire at the Sheskharis/Grushovaya oil complex near Novorossiysk on 8 June (Meduza, 8 Jun 2026); AP reported a 13 June fire at a Volna Black Sea export terminal handling crude, products and LPG (AP, 13 Jun 2026); and AP reported 21 June strikes on a Crimean oil depot, a Krasnodar oil transport facility, and a Chushka Black Sea oil terminal (AP, 21 Jun 2026). These attacks raise the right tail, but none of those reports quantified a sustained June outage at Primorsk, Ust-Luga, Novorossiysk or Kozmino.

I separate the source path from the physical state. I put 75% weight on the fallback path: 63% on a high-export case centered near 24.5%, and 12% on a weaker-flow case centered near 31.5%. I put 21% on a primary Reuters/Bloomberg capacity stocktake, mostly a strict physical-capacity interpretation centered near 8%, with a small moderate mode near 18%. I put 4% on a severe late-June disruption or broad capacity-attribution article centered near 41%. This mixture gives a median of 24.1%, mean of 22.9%, 12% probability below 10%, 29% probability above 25%, and 2.6% probability above 40%.

What's non-obvious

The obvious story is that Ukrainian strikes should lower crude exports. In June, refinery strikes often did the opposite. When Russian refineries were damaged or short of usable capacity, crude that would have been processed domestically moved to export terminals instead; Bloomberg said refinery damage helped push seaborne crude exports higher, and Reuters said first-half June western-port loadings beat the earlier plan for the same reason (Bloomberg via The Moscow Times, 2 Jun 2026; Reuters via Baird Maritime, 17 Jun 2026).

The harder point is a resolution artifact. A clean Reuters or Bloomberg stocktake of physical capacity offline would probably land in the high single digits or low teens. If no such stocktake appears by 14 July, the fallback likely resolves in the low-to-mid 20s because it compares actual exports with a 5.0 mb/d capacity baseline, even though Russia's normal actual seaborne crude exports were only 3.47 mb/d in 2025 (IEA Oil Market Report, 13 May 2026).

Limitations

The largest gap is source-path uncertainty. I did not find, as of 21 June at 19:00 UTC, a Reuters or Bloomberg end-June article that explicitly quantifies June-average crude export loading capacity offline due to Ukrainian action. If one appears, it can supersede the fallback and pull the result toward the lower physical-capacity estimate.

The second gap is terminal-level measurement. Public sources expose tanker flows, total exports, port suspensions, refinery throughput and fires, but not a daily June engineering-capacity series by berth, storage tank and pipeline feed for Primorsk, Ust-Luga, Novorossiysk and Kozmino. The final week from 22-28 June can still move the number, especially if a fresh strike pauses a primary crude terminal rather than a refinery, product depot or smaller Black Sea facility.