The US Senate voted 86-12 this week to advance a Russia-Iran sanctions bill that could impose 100% tariffs on countries importing Russian oil — and India, the largest buyer of Russian crude since 2022, is squarely in the crosshairs. Markets shrugged it off on Wednesday, with the Sensex surging 900 points on IT buying. But for India's oil refiners, this bill is an existential question: what happens when the crude that rebuilt your margins suddenly comes with a 100% price tag?

We dug into the actual filings of India's major refiners to answer a simple question: who is really exposed, and who has been quietly preparing for this moment?

The Refiners Most at Risk

MRPL (Mangalore Refinery) is the name that should worry investors the most. Per its FY 2025-26 annual report, MRPL processed 16.774 MMT of crude oil at 111.8% capacity utilization, with a GRM of $9.22/bbl — a dramatic recovery from just $4.45/bbl in FY25. That margin improvement drove profit after tax from a bare Rs 51 crore in FY25 to Rs 1,931 crore in FY26.

But look at what fueled that turnaround. MRPL's FY25 annual report lists new Russian crude grades it processed during the year: Kaliningrad, Varandey, and Sandibinskaya — all sourced from Russia. Its MD told analysts on the Q1 FY26 earnings call: "sourcing of our Russian crudes is more or in line with what the Indian industry is today sourcing." The company's own risk disclosures in its FY26 annual report acknowledge "geopolitical tensions and imposed trade sanctions impacting MRPL's financial transactions and availability of required crude grades" as a material risk. MRPL says it mitigates this through "strategic crude sourcing includes deals with global oil majors for diversification beyond traditional regions" — but with a market cap of just Rs 26,377 crore, any disruption to its crude supply hits harder here than anywhere else.

Chennai Petroleum (CHENNPETRO) tells a similar story. On its FY25 earnings call, management disclosed that "opportunity crude" — the industry euphemism for Russian barrels — was around 30% of its total crude basket. In FY24, the breakdown was explicit: Middle East ~47%, indigenous 13%, African 9-10%, and the remaining ~30% was spot crude including Russian grades. In FY23, Q4 Russian crude was 17% of throughput, with the company acknowledging capacity to take 20-25%.

The good news: CHENNPETRO is actively diversifying. Management noted they are "getting some good offers in other opportunity basket like US, African and others," suggesting the composition is shifting even if the overall volume stays the same. The company's GRM recovered sharply to $8.78/bbl in Q1 FY27, up from $3.22/bbl a year earlier — but a forced exit from Russian crude would pressure those margins right back down.

The Giant That Can Absorb the Shock

Reliance Industries operates the world's largest single-location refinery complex at Jamnagar. Its Q1 FY27 investor presentation explicitly states the company has a "diversified crude basket with higher sourcing from Russia and LatAm reducing dependence on AG [Arabian Gulf] crudes." On its Q1 FY27 earnings call, management described sourcing crude from "Latin America, US, Canada, Africa, Russia" simultaneously while running the refinery at near-full capacity with 18.1 MMT of throughput.

Reliance has the scale, the complexity, and the global trading operation to pivot crude sources faster than any PSU refiner. Its Jamnagar complex can process crudes ranging from ultra-light US shale oil to heavy Venezuelan and Colombian grades. If Russian barrels become prohibitively expensive, Reliance is best positioned to substitute — which is exactly what investors should want to hear from a company with a Rs 9.1 lakh crore market cap.

The Domestic Producers Everyone Forgets

If India is forced to reduce Russian crude imports, domestic production becomes strategically more valuable overnight. Oil India Limited delivered standalone revenue of Rs 23,987 crore and PAT of Rs 7,039 crore in FY25, with crude production of 3.46 MMT. In FY26, standalone total income held at Rs 24,039 crore and PAT was Rs 4,455 crore despite an 18% decline in crude realization prices. Oil India is already investing for growth, with Rs 8,467 crore in CapEx commitments in FY25 alone.

Any policy push to boost domestic crude production — and this sanctions bill would provide exactly that impetus — directly benefits Oil India and ONGC, whose barrels carry zero sanctions risk.

The Unexpected Winner: GE Shipping

Here is the angle nobody is talking about. The Great Eastern Shipping Company (GESHIP) has been a direct beneficiary of every round of Russia sanctions since 2022. Per its FY24 annual report: "The structural dislocation caused by Russia's invasion of Ukraine continues to benefit the Aframax and Suezmax tanker segments." Its FY23 annual report noted that Russian oil flowing to India and China on "longer voyages" was "driving higher ton miles and consequently higher freight rates."

The numbers are striking. In Q4 FY26, GE Shipping's crude carrier average daily earnings surged to $61,424/day — up 98% year-on-year from $31,002/day. If the US sanctions bill forces India to source crude from the Atlantic basin, Latin America, or the US Gulf instead of nearby Russian ports, voyage distances increase dramatically — and tanker rates go with them. The crude tanker orderbook sits at just 11% of the fleet, meaning supply cannot respond quickly. GE Shipping reported FY25 consolidated revenue of Rs 6,157 crore and net profit of Rs 2,344 crore, with 13 consecutive quarters of dividends.

Whether India pivots away from Russian crude or continues buying it through more complex routing, GE Shipping wins either way.

What Retail Investors Should Do

Don't panic-sell oil refiner stocks on the headline. The US Senate bill still needs to pass the House, and India-US trade negotiations are ongoing — Commerce Minister Piyush Goyal said this week that the first tranche of the India-US trade deal awaits "comparative tariff advantage." But do assess your portfolio's exposure to Russian crude dependence. MRPL and CHENNPETRO have the most concentrated risk. Reliance has the diversification to manage the transition. And if you're looking for a hedge against oil supply chain disruption, shipping companies like GE Shipping and domestic producers like Oil India are positioned to benefit regardless of which way the sanctions fall.

Data sourced from company filings on NSE via Xaro.