Mallon Oil
Operator of record for 36 catalogued wells across 5 states. Every well below links to its full registry page.
Filed as: MALLON OIL CO. · MALLON OIL COMPANY · Mallon Oil Company
At a glance
Mallon Oil is the operator of record for 36 catalogued U.S. oil & gas wells in 5 states. None is listed as active, 35 (97%) are plugged & abandoned. Its largest concentration is in Wyoming, with 12 wells (33% of its portfolio).
Wells operated
36
Active
0
Plugged
35
Orphaned
0
Portfolio by state
| State | Wells |
|---|---|
| Wyoming | 12 |
| Montana | 8 |
| Colorado | 7 |
| North Dakota | 5 |
| Kansas | 4 |
Well mix
- Oil wells
- 18
- Gas wells
- 2
- Shut-in
- 0
- Active share
- 0%
Is this your company?
Claim Mallon Oil to keep this portfolio accurate — verified operators can correct well statuses and add plugging documentation.
Claim your operator profileWhere does Mallon Oil operate?
Mallon Oil's catalogued wells are spread across 5 states: Wyoming (12), Montana (8), Colorado (7), North Dakota (5) and Kansas (4). Its 8 Montana wells are 0.0% of the 42,011 catalogued in that state — its largest share of any state. Counts cover only states whose registries WellCensus has ingested with operator names; wells in Nebraska and Texas (location indexes) and in states without a registry ingest are not yet attributed to any operator.
How many of Mallon Oil’s wells are active, plugged or orphaned?
0% of Mallon Oil's catalogued wells are active, 29 percentage points below the national share of 29%. 97% are plugged & abandoned, against 47% nationally. None of the wells filed under this name is flagged as orphaned.
What kinds of wells does Mallon Oil operate?
By product class, 18 (50%) are oil wells and 2 (6%) gas wells; nationally the shares are 43% and 17%. The deepest of its wells with a published depth is Mallon-Federal 32-11 in Washakie, WY at 11,663 ft. The wells listed below sit in Washakie (WY), Laramie (WY), Roosevelt (MT), Campbell (WY), Crook (WY) and Musselshell (MT) and other counties. State filings spell the name 3 ways; WellCensus merges exact-normalized spellings only, so subsidiaries and affiliates keep their own pages.
Notable wells operated by Mallon Oil
| Well | API # / state ID | Status | Type | Location | Operator | Depth |
|---|---|---|---|---|---|---|
| Mallon-Federal 32-11 | 49-043-20553 | Plugged & abandoned | Oil | Washakie, WY | Mallon Oil Company | 11,663 ft |
| Pence Ranch 16-2 | 49-021-60012 | Plugged & abandoned | Oil | Laramie, WY | Mallon Oil Company | 8,121 ft |
| Pence Ranch 16-3 | 49-021-20214 | Plugged & abandoned | Oil | Laramie, WY | Mallon Oil Company | 8,115 ft |
| Hawbaker 27-1 | 25-085-21158 | Plugged & abandoned | Other type | Roosevelt, MT | Mallon Oil Company | 7,833 ft |
| Federal 21 32-30 | 49-005-20915 | Plugged & abandoned | Oil | Campbell, WY | Mallon Oil Company | 7,800 ft |
| Tribal 1-28 | 25-085-21258 | Plugged & abandoned | Other type | Roosevelt, MT | Mallon Oil Company | 7,800 ft |
| Pence Ranch Co 15-1 | 49-021-20206 | Plugged & abandoned | Oil | Laramie, WY | Mallon Oil Company | 7,670 ft |
| Toavs 33-1 | 25-085-21157 | Plugged & abandoned | Other type | Roosevelt, MT | Mallon Oil Company | 7,430 ft |
| Mallon Watson Fee 1-1 | 49-011-20778 | Plugged & abandoned | Oil | Crook, WY | Mallon Oil Company | 7,275 ft |
| Svalina Fee 13-5 | 49-005-26322 | Plugged & abandoned | Oil | Campbell, WY | Mallon Oil Company | 7,265 ft |
| Roberts 31-10 | 25-065-21663 | Plugged & abandoned | Other type | Musselshell, MT | Mallon Oil Company | 7,025 ft |
| Smith 7-9 | 25-105-21245 | Plugged & abandoned | Other type | Valley, MT | Mallon Oil Company | 6,997 ft |
Deepest first where depth is published. See all 36 wells →
Frequently asked questions
How many wells does Mallon Oil operate?
Mallon Oil is the operator of record for 36 catalogued oil & gas wells, with the largest concentration in Wyoming (12). Only wells in states WellCensus has ingested are counted.
How many of Mallon Oil's wells are still active?
0 of Mallon Oil's catalogued wells are active; 35 are plugged & abandoned.
In which states does Mallon Oil operate wells?
Mallon Oil is the operator of record for wells in Wyoming (12), Montana (8), Colorado (7), North Dakota (5) and Kansas (4).
Does Mallon Oil operate mostly oil or gas wells?
18 of Mallon Oil's catalogued wells are oil wells and 2 are gas wells; the rest are injection, service or unclassified wells.
What is Mallon Oil's deepest well?
Among wells with a published depth, Mallon-Federal 32-11 in Washakie, WY is the deepest at 11,663 ft.
Where Mallon Oil's wells are
- Oil & gas wells in Wyoming· 12 operated by Mallon Oil
- Oil & gas wells in Montana· 8 operated by Mallon Oil
- Oil & gas wells in Colorado· 7 operated by Mallon Oil
- Oil & gas wells in North Dakota· 5 operated by Mallon Oil
- Oil & gas wells in Kansas· 4 operated by Mallon Oil
- Largest U.S. well operators
- All well operators
About this data
Source: State oil & gas regulator registries (operator of record as filed, exact-normalized across states) plus the USGS United States Documented Orphaned Well Database (2026), as published October 10, 2026 — WellCensus refreshes it monthly. See the methodology for how records are matched, cleaned and scored.
Cite as: WellCensus, “Mallon Oil — well portfolio”, https://wellcensus.com/operators/mallon-oil-10993 (data as of October 10, 2026).
Dataset updated . Operator portfolios are resolved from raw state registry filings (exact-normalized names; subsidiaries stay separate).