Oil: Private survey of inventory shows a large headline crude oil draw vs. build expected

The inventory data referenced here comes from a privately conducted survey by the American Petroleum Institute (API), which polls oil storage facilities, refiners, and other industry participants on a voluntary basis. The API report is typically released late Tuesday US time and is widely viewed as a preliminary indicator of changes in US crude oil inventories ahead of the official government figures.

By contrast, the more authoritative data is published by the US Energy Information Administration (EIA) on Wednesday morning US time. The EIA report is based on mandatory submissions and data collected by the Department of Energy and other government agencies, making it broader in scope and generally more reliable.

While the API report focuses primarily on headline changes in crude oil storage levels and week-on-week variations, the EIA release provides a much more comprehensive snapshot of oil market conditions. In addition to total crude inventories, it includes detailed information on refinery inputs and outputs, utilisation rates, gasoline and distillate stocks, imports and exports, and storage levels across different grades of crude oil, such as light, medium, and heavy blends.

As a result, the EIA report is considered the definitive reference point for oil traders and analysts, with greater market impact, particularly when it diverges from API estimates. Discrepancies between the two reports are common and can trigger short-term volatility in oil prices, as markets reassess supply-demand balances once the official data is released. For this reason, the API figures are best viewed as a directional guide rather than a substitute for the EIA’s official assessment of US oil inventories.