US Threatens 100% Tariff on India's Russian Oil — Which Refiners Are Most Exposed?

A bill making its way through the US Senate could impose 100% tariffs on countries that import Russian crude oil — and India, which has become Russia's largest seaborne crude buyer since 2022, is squarely in the crosshairs. White House trade adviser Peter Navarro acknowledged the backlash, telling the Economic Times he "got firebombed by Indians" over the proposal, while assuring that "Trump and Modi will work it out."

But for retail investors holding oil refining stocks, the question isn't whether diplomats will find a deal — it's which companies have the most to lose if they don't. We dug into corporate filings across India's major refiners to map the exposure.

Chennai Petroleum: The Most Exposed

Chennai Petroleum Corporation (CHENNPETRO) stands out as the refiner with the highest disclosed Russian crude dependency. In their FY26 earnings call, Director Finance Rohit Agrawala broke down the crude basket: Middle East accounts for roughly 47%, indigenous crude 13%, West African 9-10%, with the remaining ~30% coming from "opportunity crudes" — which he acknowledged are "predominantly represented by Russian crudes" in recent years.

CHENNPETRO's ability to process over 150 grades of crude gives it flexibility, but 30% is a significant share to replace at short notice. The company's Q1 FY27 results (board outcome filed July 2026) show EPS of Rs 68.27, down from Rs 94.00 in Q1 FY26 — already under pressure before any tariff materialises.

MRPL: "Marginal" But in Line With Industry

Mangalore Refinery and Petrochemicals (MRPL) has been more guarded. In their January 2026 earnings call, the management stated that "Russian crude were opportunity crudes. They always played a marginal role in our overall strategy." MD Shyamprasad Kamath added that the "loss of Russian barrels is not going to make a significant kind of an impact."

However, when pressed on specifics, Kamath conceded that MRPL's Russian crude sourcing is "more or in line with what the Indian industry is today sourcing" — suggesting it's far from negligible. MRPL's FY25 was already tough: the company earned just Rs 51 crore in profit after tax, down sharply from Rs 3,596 crore the prior year, with the GRM falling to $4.45 per barrel. Any loss of discounted Russian crude would put further pressure on already thin margins.

BPCL: Heavy on High-Sulphur, Dependent on Discounts

Bharat Petroleum (BPCL) doesn't disclose Russian crude percentages specifically, but their filings reveal a telling detail: high-sulphur crude consistently makes up 75-77% of their total crude intake, per their investor presentations through FY26. High-sulphur grades are precisely the type Russia has been selling at steep discounts.

The good news for BPCL shareholders: the company's GRM has recently recovered strongly. H1 FY27 showed GRM of $10.78 per barrel (overall), with the Bina refinery hitting $15.93 per barrel — a sharp rebound from Q1 FY26's $4.88. This suggests BPCL's complex refinery configuration can extract value even as the crude slate shifts.

HPCL: Diversified but Watching the Strait

Hindustan Petroleum (HPCL) imported 22.08 MMT of crude in FY26, supplemented by 4.14 MMT from indigenous sources, per their July 2026 annual report. Their portfolio included 16.27 MMT of high-sulphur and 5.81 MMT of low-sulphur crude. HPCL explicitly lists "diversification of crude oil sourcing" as a key risk mitigation strategy, and has been investing in strategic crude storage capacity.

HPCL is already grappling with the aftershock of the Strait of Hormuz disruption. Their annual report notes that the Indian crude basket spiked to $113.5 per barrel in March 2026 when the Strait was effectively closed. Any Russian tariff would layer additional sourcing constraints on top of an already volatile supply picture.

Reliance: Best Positioned to Adapt

Reliance Industries, with its world-class Jamnagar complex, has the strongest hand. Their FY26 investor presentation shows the company already navigated a severe supply shock when 40-50% of the crude volume it typically sourced from the Middle East was disrupted during the Strait of Hormuz crisis. The company pivoted to "maximising arbitrage barrel sourcing" and maintained operations.

Reliance's presentation for FY26 also notes that "US and EU sanctions tightened on Russian crude though relaxed in Mar '26" — the company was already adapting its feedstock mix well before this tariff threat. With India's largest refining capacity and the ability to process virtually any crude grade, Reliance is the refiner least likely to be hurt.

The Unexpected Winner: Great Eastern Shipping

Here is the angle most analysts are not watching. Great Eastern Shipping (GESHIP) has documented in multiple annual reports and earnings calls that Russian crude re-routing has been a structural tailwind for tanker companies. Their FY23 annual report stated it directly: "Russia's oil exports have seen longer voyages, particularly flowing to India and China. This has benefited Suezmax and Aframax tanker segments, driving higher ton miles and consequently higher freight rates."

In their August 2026 earnings call, GESHIP management noted that "events around the Strait of Hormuz had a huge impact on tanker markets — we saw freight rates going to all-time highs during the last quarter." If a 100% US tariff forces India to find alternative crude sources from further afield — say the US Gulf, West Africa, or Latin America — that means even longer voyages and even better freight economics for tanker operators.

What Retail Investors Should Do

Don't panic-sell refiners over this headline — the bill still needs to pass, and both governments have signalled willingness to negotiate. But do understand your exposure:

Watch CHENNPETRO's next earnings call closely for any change in their 30% opportunity crude disclosure. That number is the canary in the coal mine. Data sourced from company filings on NSE via Xaro.