Japan's oil supply just had its worst month since the Carter administration, and the May rebound is already in the tankers.
Middle East crude shipments into Japan collapsed 67.2% in April compared with April 2025, which is the lowest level since data collection began in 1979.
May is set to recover meaningfully - but not because the Strait of Hormuz has reopened.
Japan's May crude imports are tracking at around 1.7 million barrels per day, according to vessel-tracking data through May 19. That's roughly three-quarters of where imports sat a year ago.
The recovery is being built around the Strait of Hormuz, not through it - by May, Japan should be getting more than half of its oil via routes that skip the strait entirely.
A barrel of oil is about 42 gallons, and Japan burns through millions of them a day. When the usual route closes, refiners have weeks, not months, to find another.
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The single biggest swing factor is the US, with Japanese refiners pulling four times more crude from American producers in May than they did a year ago.
Saudi shipments via the Red Sea are filling more of the gap, while Japan has also been quietly working the phones with suppliers in Malaysia, Azerbaijan, Brazil, Nigeria, and Angola.
Tokyo also approved an extra 20 days of strategic reserve releases starting in May, part of an 80-million-barrel plan to bridge the gap.
The vessel-tracking number for May is likely to come in above what Japan's own government forecast, because refiners arranged independent supplies on top of what officials had lined up.
In plain terms: companies didn't wait for a national plan, and went and bought oil where they could find it.
Whether Hormuz stays effectively closed is the variable that decides everything. As long as it does, expect more US and African barrels heading east - and a higher floor under those producers' export revenue.
A 1.7 million-barrel-a-day rebound is real progress, even though it's still a million barrels a day short of normal.
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