The arrivals brought Iran to the seventh position in 2018, with shipments of 29.27 million tons, or 587,881 bpd, for the entire year, reported spglobal.com on Friday.
There has been a clear trend since October that an increasing proportion of shipments from Iran were flowing into storage tanks instead of going to refineries.
About a three-fifth of the Iranian arrivals in December flowed into stocks, market sources said. Some of them went into strategic petroleum reserve tanks in northeastern Jinzhou and southern Huizhou.
Bonded storage in northeastern Dalian, where the Iranian state-owned NIOC leased storage tanks are located, also witnessed inflows in December, indicating that efforts were made to stockpile Iranian crude.
However, most of the Iranian barrels arriving in January are likely to go to Maoming, Ningbo, Qingdao and Tianjin, where Sinopec's refineries are located, S&P Global Platts' trade tracker cFlow showed on Friday.