S7 Airlines, Russia’s largest private airline, was suspended from the oneworld alliance in 2022 following the invasion of Ukraine, and the suspension remains in place. That means the old method of booking S7 with British Airways Avios, American miles, or any other oneworld currency no longer works.

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S7 flights cannot be searched or booked through any oneworld partner program. Western sanctions also mean the usual points ecosystems, from bank transfer partners to alliance bookings, do not touch Russian domestic aviation.
If your goal is reaching destinations S7 used to serve with partner miles, the practical routes today run through other alliances’ hubs, such as Istanbul with Turkish Airlines (Star Alliance) or Middle East connections, subject to current travel advisories.