# What is a drilled but uncompleted well?

Canonical source: https://www.wildcatters.co/learn/what-are-ducs
Publisher: Wildcatters (https://www.wildcatters.co/#organization)
Content type: Learn concept / guide
Source/provenance: Wildcatters editorial explanation with the regulator and primary references listed below.
Modified: 2026-09-11
Snapshot retrieved: 2026-09-12T11:33:04.209Z
Limitations: Historical examples and source reporting dates are not current prices or proof of ownership. Check source records and property documents.

A drilled but uncompleted well, or DUC, has been drilled but has not completed the work needed to begin production. DUC status does not establish a production start date; completion timing can vary substantially.

# What is a drilled but uncompleted well?

A drilled but uncompleted well, or DUC, has been drilled but has not completed the work needed to begin production. DUC status does not establish a production start date; completion timing can vary substantially.

Updated: 2026-09-11. By Wildcatters Editorial.

## What to know

- Drilling and completion are different stages.
- DUC status does not guarantee future output or timing.
- An aggregate inventory is not a status report for your well.

## Development or preparation sequence

1. **Permit:** Permission for the proposed work
2. **Spud:** Drilling operations begin
3. **Drilling:** The wellbore is constructed
4. **Completion:** Work to prepare the well for production
5. **Production:** Oil or gas is produced and reported

## Drilling creates the wellbore; completion prepares it

Drilling constructs the wellbore. Completion involves the work and equipment needed to prepare it for production. The [EIA completion glossary](https://www.eia.gov/tools/glossary/index.php?id=Completion+(oil/gas+production)) provides terminology for this stage.

The required work depends on the well and reservoir. Do not assume that every DUC is a horizontal shale well or requires the same fracturing program. A [spud date](https://www.wildcatters.co/learn/understanding-spuds) marks the start of drilling; it is not the date drilling or completion finished.

## Why completion can be delayed

Drilling and completion can use different crews, equipment, and schedules. Operators may sequence work across multiple wells or postpone a completion for operational or economic reasons.

EIA’s [2019 North Dakota analysis](https://www.eia.gov/todayinenergy/detail.php?id=41253) documents completion delays and discusses scheduling flexibility and economic conditions. Its historical observations do not establish the timing or economics of a particular well today. The reason for an individual delay should come from that well’s records or the operator, not from the DUC label alone.

## What DUC status does and does not establish

| A DUC description can indicate | It does not establish |
| --- | --- |
| Drilling has occurred and completion remains outstanding under the source’s definition | A promised completion or first-production date |
| A point in the reported development sequence | A producing well or a revenue stream |
| An observation at a particular reporting date | The current field condition after that date |
| Part of an aggregate inventory | A guaranteed amount of future supply or demand for drilling rigs |

An inventory count must be interpreted using its coverage, definitions, and observation period. Do not infer one property’s completion status from a basin total.

## How to research the underlying well

1. **Match the well.** Record the state, name, operator, and official identifier.
2. **Check the dates.** Distinguish the spud date, drilling completion, completion work, and the date a record was filed or retrieved.
3. **Read the available filings.** Look for completion reports and subsequent production records. The [RRC research queries](https://www.rrc.texas.gov/resource-center/research/research-queries/) provide Texas permit, completion, and other research entry points.
4. **Keep production periods attached.** A historical reported volume is not a live field reading.
5. **Record uncertainty.** Missing or delayed filings do not prove that no work has occurred.

Use [Intelligence 2.0](https://www.wildcatters.co/intelligence-2) to start with a connected jurisdiction. Where coverage does not support the required record, use the regulator’s source and state what remains unverified.

## Questions about a well that remains uncompleted

### Will every DUC eventually produce?
The label does not guarantee that a well will be completed or produce commercially. It describes a development status, not a commitment or performance forecast.

### Does completion mean the first royalty payment is due?
Completion, reported production, sales, and owner payments are different events. Payment questions also depend on the relevant ownership and payment documents.

### Can a DUC count predict new production next month?
A count by itself does not supply a completion schedule or expected production rate for each well. Additional evidence is needed before making a forecast.

## Find the next record in the well’s history

Check completion and production reporting for the well, keeping the source and observation dates together.

[Research a well](https://www.wildcatters.co/intelligence-2)

## Related reading

- [What does spud mean?](https://www.wildcatters.co/learn/understanding-spuds)
- [Understand working interests](https://www.wildcatters.co/learn/what-are-working-interests)

## Sources

- [EIA · Completion terminology](https://www.eia.gov/tools/glossary/index.php?id=Completion+(oil/gas+production))
- [EIA · Completion delays (2019)](https://www.eia.gov/todayinenergy/detail.php?id=41253)
- [Texas RRC · Research queries](https://www.rrc.texas.gov/resource-center/research/research-queries/)