# Crude oil days of supply | PIER20 benchmarks

How many days of crude oil supply does the U.S. hold, and where does that sit seasonally?

This page shows U.S. days of supply of crude oil excluding the SPR (EIA series W_EPC0_VSD_NUS_DAYS).  Each week is compared to the same week in the five full years before that week.  The chart shows the five-year average, minimum, and maximum.  A reading above the five-year range is high for the season. A reading below is low for the season.  Days of supply fall when refinery demand runs above stock builds and rise when stocks outpace runs.  This is a seasonal gauge. It is not a price forecast. 

As of **31 July 2026**, the latest reading is **23.70 Number of Days**. That is down 5.2% over the past year and above its long-run median of 23.50 Number of Days.

## Summary statistics (full history)

| Series | First | Latest | Min | Max |
|---|---|---|---|---|
| Days of supply | 28.90 | 23.70 | 16.10 | 42.00 |
| Five-year average |  | 26.33 | 17.41 | 31.87 |
| Five-year minimum |  | 25.07 | 16.40 | 27.83 |
| Five-year maximum |  | 27.37 | 18.70 | 41.73 |

## Last 24 readings

| Date | Days of supply | Five-year average | Five-year minimum | Five-year maximum |
|---|---|---|---|---|
| 20 Feb 2026 | 27.30 | 30.84 | 27.13 | 36.93 |
| 27 Feb 2026 | 27.60 | 31.39 | 27.03 | 39.93 |
| 6 Mar 2026 | 27.80 | 31.44 | 26.87 | 40.83 |
| 13 Mar 2026 | 28.10 | 30.89 | 26.57 | 39.47 |
| 20 Mar 2026 | 28.10 | 30.16 | 26.23 | 37.03 |
| 27 Mar 2026 | 28.20 | 29.61 | 26.27 | 34.67 |
| 3 Apr 2026 | 28.40 | 29.38 | 26.30 | 33.53 |
| 10 Apr 2026 | 28.40 | 29.26 | 26.43 | 33.00 |
| 17 Apr 2026 | 28.80 | 29.13 | 26.43 | 32.73 |
| 24 Apr 2026 | 28.60 | 29.07 | 26.73 | 32.50 |
| 1 May 2026 | 28.50 | 29.01 | 26.87 | 32.27 |
| 8 May 2026 | 28.10 | 28.86 | 26.80 | 32.17 |
| 15 May 2026 | 27.50 | 28.55 | 26.40 | 31.87 |
| 22 May 2026 | 26.90 | 28.13 | 26.07 | 31.33 |
| 29 May 2026 | 26.10 | 27.71 | 25.83 | 30.53 |
| 5 Jun 2026 | 25.40 | 27.29 | 25.70 | 29.63 |
| 12 Jun 2026 | 24.60 | 26.91 | 25.07 | 28.77 |
| 19 Jun 2026 | 24.20 | 26.61 | 24.67 | 28.07 |
| 26 Jun 2026 | 23.90 | 26.49 | 24.70 | 27.73 |
| 3 Jul 2026 | 24.00 | 26.46 | 24.87 | 27.87 |
| 10 Jul 2026 | 23.90 | 26.41 | 24.90 | 27.90 |
| 17 Jul 2026 | 24.10 | 26.34 | 24.93 | 27.43 |
| 24 Jul 2026 | 23.60 | 26.35 | 24.97 | 27.37 |
| 31 Jul 2026 | 23.70 | 26.33 | 25.07 | 27.37 |

## How to read this benchmark

**What a high or low reading means.** Days of supply converts the stock level into run coverage: how long commercial crude stocks would last at current refinery consumption. A high seasonal reading means the barrel backlog is large relative to the refining calendar. Slack supply, bearish for crude. A low reading means refiners are chewing through inventories faster than usual, which has historically supported prompt prices. The unit removes the market's growth: the number is comparable across decades even as barrels grow. 

**Why the five-year same-week average as the comparator.** Energy series move with the calendar year.  A raw level cannot say if the market is tight or slack.  This page ranks each week against the same week in the five full years before it.  A July reading is judged against prior Julys, not against the full year.  The baseline uses only earlier years.  The current year never enters its own baseline.  The rule allows one week of tolerance when holidays shift the report week. 

**How the seasonal lines are built.** For each date, the reference is the same EIA week number (plus or minus one week) in the five full calendar years before it.  Each reference year adds one value (the mean of its tolerated observations).  The average, minimum, and maximum use those five yearly values.  The lines start once a five-year window exists.  The window rolls forward as old years leave. 

**Limitations.** The five-year window moves as history rolls forward, so an extreme from a decade ago no longer anchors the range.  Source revisions can move history.  Days of crude supply is one input to the market balance.  Prices also move on the weekly surprise versus expectations, not on the level alone.  Treat the chart as context for supply and demand conditions, not investment advice. 

## How this benchmark is used

**The run-coverage convention.** Refiners and traders express stock adequacy as days of cover. The run rate is the denominator, not the barrel count. Because a barrel is only worth as much as the demand it serves. Days of supply is the same convention EIA publishes in the WPSR, so this page is directly comparable to the report's own framing of inventory adequacy. 

**The EIA five-year range convention.** The Weekly Petroleum Status Report uses a five-year average and range.  The Weekly Natural Gas Storage Report does the same for gas.  This page uses the same idea with a strict same-week rule.  It uses five full prior years and allows one week of tolerance.  The current year never enters the baseline.  Our average can differ slightly from EIA tables when holiday weeks differ. 

## Frequently asked questions

**What is the current crude oil days of supply?**

As of 31 July 2026, the latest reading is 23.70 Number of Days. That is down 5.2% over the past year and above its long-run median of 23.50 Number of Days.

**How often is this benchmark updated?**

This benchmark is built on weekly data. The page is refreshed when the source publishes new observations; the freshness block below the chart shows the exact data-through date and when PIER20 last fetched the file.

**What data sources does this chart use?**

The chart is built from Days of supply, Five-year average, Five-year minimum and Five-year maximum, sourced from the U.S. Energy Information Administration (EIA).

**What is the highest and lowest Days of crude supply has reached?**

The percentile cell ranks the latest reading against the full sample.  The 100th percentile is the highest on record.  The 0th is the lowest.  The five-year range is relative.  Read full-history extremes on the full chart range, not only on the seasonal range. 

**How is this different from commercial crude inventories?**

This page divides stocks by refinery throughput . EIA publishes it directly as days of supply. The inventories page shows raw barrels, which grow with the size of the market over time; days of supply normalizes that growth out, so the two can disagree: stocks at a record can still be only average days of supply if runs are also at records. 

**Why does the five-year range only start five years into the history?**

A baseline needs five full prior years of observations.  The current year never enters its own baseline.  The first five years of a series have no complete reference window.  Earlier readings plot without a seasonal reference. 

## Methodology

- Formula: seasonalReference(t) = same EIA week (±1 week) in the five complete years before t; average/min/max of the per-year values
- Frequency: Weekly
- Sources: Days of supply (W_EPC0_VSD_NUS_DAYS) https://www.eia.gov/dnav/pet/hist/LeafHandler.ashx?n=PET&s=W_EPC0_VSD_NUS_DAYS&f=W; Five-year average (W_EPC0_VSD_NUS_DAYS#seasonalAvg) https://www.eia.gov/dnav/pet/hist/LeafHandler.ashx?n=PET&s=W_EPC0_VSD_NUS_DAYS&f=W; Five-year minimum (W_EPC0_VSD_NUS_DAYS#seasonalLow) https://www.eia.gov/dnav/pet/hist/LeafHandler.ashx?n=PET&s=W_EPC0_VSD_NUS_DAYS&f=W; Five-year maximum (W_EPC0_VSD_NUS_DAYS#seasonalHigh) https://www.eia.gov/dnav/pet/hist/LeafHandler.ashx?n=PET&s=W_EPC0_VSD_NUS_DAYS&f=W. Data via the U.S. Energy Information Administration (EIA).
- Data through: 31 July 2026
- Last refreshed: 11 Aug 2026

Full interactive chart: https://pier20.com/benchmarks/crude-inventory-days-supply
Disclaimer: research software output, not investment advice.
