Iran's obol
Stablecoins buy safe passage in the Strait of Hormuz
In Greek mythology, Charon’s obol was a coin placed in the mouth of the dead to bribe the ferryman, Charon, to give a soul safe passage across the River Styx. The obol was a silver coin worth one sixth of a drachma.
On Wednesday, Bloomberg reported that Iran is accepting tolls in Chinese renminbi — or stablecoins — to assure the safe passage of ships through the Strait of Hormuz:
For oil tankers, the starting price in the negotiations is typically around $1 per barrel of oil, paid in yuan, or stablecoins — cryptocurrencies pegged to the value of hard currency.
To paraphrase their reporting, Iran’s National Security Committee approved a bill to impose fees on ships passing through the Strait. Operators must contact an intermediary linked to Iran’s Revolutionary Guard Corps (IRGC) with detailed vessel information that is then screened for ties to Israel, the United States, or other states Iran considers hostile. Fee negotiations rely on a ranking from 1–5, with friendly countries getting better terms. This builds upon CNN’s reporting that Iran was considering only allowing tankers transporting oil traded in RMB to pass through the Strait.
Let me point out irony number one: per Bloomberg’s reporting, the fee is still assessed in dollars. I don’t think ships are paying 1 RMB per barrel of oil. Coverage is limited but it sounds like the dollar is still the unit of account. So, ships can’t pay in USD but the transaction will still be denominated in USD? Alright.
Anyway, given that a Very Large Crude Carrier holds roughly 2 million barrels, a single tanker could face fees starting at $2 million per transit. If these tolls (bribes) are being paid in RMB, that’s a lot of RMB. In an analysis of China’s cross-border RMB payment system, CIPS, Alisha Chhangani at the Atlantic Council writes:
GeoEconomics Center analysis of CIPS data shows in the chart below that monthly averages for daily transaction volume remained within a $85–105 billion (600–750 billion yuan) range over the past year. In mid-to-late March, however, daily observations rose to over $130 billion (around 940 billion yuan). On April 1, CIPS reported that the daily average transaction volume in March reached $134 billion, or 920.45 billion yuan.
That is a nearly 60% increase of cross-border RMB volume from the lower bound. Chhangani also notes that not all of this volume is from the (relatively new) tolling system, but the timing is interesting in the context of the war.
Stable passage
So, what about tolls slash bribes paid in stablecoins (98% of which are pegged to the U.S. dollar)? If the toll slash bribe system proves durable, my guess is that China and its closest trading partners will opt to pay in RMB. Countries without significant RMB payment infrastructure (i.e. anyone who is not a direct or indirect participant in CIPS) will probably pay in stablecoins.
So we should be watching for a few signals in stablecoin settlement volume:
Aggregate stablecoin volume: According to Artemis, a blockchain analytics firm, stablecoin volume on March 30th hit $321 billion. This is well within the 30-day range, suggesting that the volume has not substantially picked up yet.
Specific on-chain data: Increases in on-chain transactions in stablecoins on specific networks favored by Iran (like USDT on Tron) could suggest more durable usage. An academic paper from 2025 stated USDT on Tron accounted for approximately 72% of Iranian stablecoin activity.
Large one-off transactions: The sudden appearance of individual large stablecoin transfers (over $1 million) that can be directly correlated to real-time transit of a vessel.
Irony number two is not just that the U.S. dollar are the unit of account in assessing the toll slash bribe, but also that it is a method of payment, via stablecoins — despite Iran previously vowing to fire upon ships carrying oil traded in dollars. Again, stablecoins are almost universally pegged to the U.S. dollar, so Iran is still accepting dollars, just dollars that don’t touch the U.S. banking system as an intermediary.
From a U.S. policy perspective, this is arguably a better outcome. Every ship that pays the IRGC’s toll slash bribe in stablecoins rather than RMB is continuing to transact in dollar-denominated assets and preserving dollar dominance in the global oil trade. Even if it’s not a trade we particularly want to support. The alternative, yuan-based payments, likely flow through CIPS and are not only opaque to the West but actively fuel China’s parallel financial system in ways that could outlast this conflict.
If Iran’s terror toll slash bribe system lasts, we should look to stablecoin volumes in the coming weeks as a proxy for dollar resilience. A world where bribes to pass physical chokepoints controlled by the United States’ enemies are priced and settled in USDT is a world where the dollar remains the unit of account for global commerce, even when the U.S. financial system is explicitly being cut out of the transaction.
For souls haggling with a psychopomp in the underworld, prospects weren’t so rosy. But in this world, life finds a way. Or, to coin a corollary, thanks to the ingenuity of the private sector through stablecoins, the dollar finds a way.1
LFG