To check a mining claim, you look it up in BLM’s Mineral & Land Records System (MLRS), the free online system that holds federal mining claim records. The quickest way is to run the “Mining Claims – Geographic Report” at reports.blm.gov/reports/MLRS with the claim’s township, range and section, which lists every active or closed claim in that spot.
The system can feel clunky the first time you use it, and it’s often slow. Once you know which report to pick and how to type in the location code, a lookup takes a few minutes.
What MLRS is
MLRS is the Bureau of Land Management’s records system for mining claims and other land cases. The main site is mlrs.blm.gov, and the public reports live at reports.blm.gov/reports/MLRS. Looking things up is free, and you don’t need an account to run the public reports.
BLM built MLRS to replace its older LR2000 system, which a lot of older prospecting guides still mention. If you see instructions that send you to LR2000, skip them and use MLRS instead. Old LR2000 serial numbers still work for searches in MLRS, so older paperwork is still useful.
What’s in the records
MLRS holds a lot of claims. Our analysis of BLM’s records found about 563,000 active mining claims across the 12 western states we map as of October 25, 2026, and about 4.17 million claims in the full history (active and closed) as of March 2025.
- About 85% of active claims are lode claims (claims on a vein or rock in place). About 13% are placer claims (loose gold in gravel and sand), and most of the rest are mill sites.
- Nevada holds almost half of all active claims, about 273,000.
- Companies hold about 90% of active claims. Individuals hold a bigger share in some gold-panning states: companies hold about 65% in California, 70% in Oregon and 64% in Washington.
Source: Gold Maps Online analysis of BLM mining claim records, October 2026 (history figures as of March 2025). These are all mining claims, not just gold, because BLM records don’t say which mineral a claim is for.
Which BLM tool to use
BLM has several ways to see claim records, and they’re good at different things.
| Tool | Good for | Keep in mind |
|---|---|---|
| Geographic Report (MLRS reports) | A list of every claim in one section, active or closed | You need the MTRS location code, typed exactly |
| Serial Register Page report (MLRS reports) | The full record for one claim | You need the claim’s serial number |
| Research Map (mlrs.blm.gov/s/research-map) | Seeing claims on a map and clicking into a record | Shows claims to the quarter section, not exact corners; some features need you to sign in |
| BLM’s GIS layers (“Mining Claims – Not Closed” and “Mining Claims – Closed”) | Loading claims into mapping software | Big downloads, and you need GIS software to use them |
| BLM state office public room or county recorder | The location notice and claim map, which show the real boundaries | Request in person or by contacting the office |
For most prospectors, the Geographic Report is the one to learn, since it answers the main question: are there active claims where you want to go?
How to read the MTRS location code
MLRS finds claims by their spot in the Public Land Survey System, the grid of townships and sections that covers most of the West. BLM writes that spot as an MTRS code, short for meridian, township, range and section. A code looks like this:
26 0290S 0130W 008
- 26 is the meridian, the survey line the grid is measured from. Each one has a two-digit BLM code (26 is the Salt Lake Meridian in Utah).
- 0290S is the township: Township 29 South.
- 0130W is the range: Range 13 West.
- 008 is the section: Section 8. A section is usually about one square mile.
BLM’s Montana office gives another example: Township 10 South, Range 6 East, Section 14 on the Principal Meridian Montana (code 20) is written as “20 0100S 0060E 014.” The zeros matter, since MLRS expects the code in exactly this format.
Here are the meridian codes BLM lists for each western state. Some states use more than one meridian, so check which one your section is on. Our map popups name it for every section.
| State | Meridian codes |
|---|---|
| Arizona | 14 Gila and Salt River, 27 San Bernardino |
| California | 21 Mount Diablo, 27 San Bernardino, 15 Humboldt, 14 Gila and Salt River |
| Colorado | 06 Sixth Principal, 23 New Mexico Principal, 31 Ute |
| Idaho | 08 Boise, 21 Mount Diablo |
| Montana | 20 Principal Meridian Montana, 05 Fifth Principal, 07 Black Hills |
| Nevada | 21 Mount Diablo, 27 San Bernardino |
| New Mexico | 23 New Mexico Principal, 14 Gila and Salt River, 26 Salt Lake |
| Oregon and Washington | 33 Willamette |
| South Dakota | 07 Black Hills, 05 Fifth Principal, 06 Sixth Principal, 20 Principal Meridian Montana |
| Utah | 26 Salt Lake, 30 Uintah Special |
| Wyoming | 06 Sixth Principal, 34 Wind River |
Source: BLM meridian code table.
Step by step: look up claims by location
- Open the reports page. Go to reports.blm.gov/reports/MLRS. Under “Public Mining Claims Reports,” click “Mining Claims – Geographic Report.”
- Pick the Admin State. This is the BLM state office that handles claims there. It’s usually the state you’re searching, with a few exceptions: claims in Washington are handled by the Oregon office, and claims in South Dakota and North Dakota by the Montana office.
- Type the MTRS code. Enter it in the “Meridian Township Range Section” box. Type it out rather than picking from the list, and hover over the box if you want BLM’s help on the format. BLM says that if your entry disappears when you click out of the box, there are no claims in that section.
- Set the Case Disposition. Tick Active and Filed to see claims people hold now, or Closed to see abandoned claims. Filed means BLM has the paperwork for a new claim but hasn’t finished processing it, so if you skip it you’ll miss the newest claims.
- Narrow it down if you want. You can pick a quarter of the section (northeast, northwest, southeast or southwest) to see only the claims in that corner.
- Click OK and wait. The report can take a while. “No Results” means no claims match, or something was typed in wrong.
- Open each claim. Click a serial number in the results to open that claim’s Serial Register Page, which is the full record for that one claim.
If you already have a serial number, you can skip the location search. The “Mining Claims – Serial Register Page (SRP)” report on the same page pulls up a single claim by its number.
A worked example from our Arizona map
Here’s a real lookup, using a section in Yavapai County, Arizona, that shows up on our Arizona gold map. Clicking the section in the active placer layer shows this popup:
- 7 active placer claims (by quarter: NE 7, NW 1)
- Newest claim staked: April 28, 2026
- Closed claims in this section: 224
- County: Yavapai
- T9N R2E Sec 8, Gila and Salt River Meridian
- BLM code (MTRS): 14 0090N 0020E 008
The other layers fill in the rest. The active lode layer shows 4 active lode claims in the same section, so there are 11 active claims in all. The closed layers show 185 closed lode claims and 39 closed placer claims, with the most recent one closing on November 17, 2022.
To check it in MLRS, open the Geographic Report, pick AZ as the Admin State, type 14 0090N 0020E 008 in the “Meridian Township Range Section” box, tick Active, Filed and Closed under Case Disposition, and click OK. We ran this lookup on October 28, 2026. MLRS listed 9 claims as Active and 2 as Filed, the two newest placer claims, staked in March and April 2026 and still being processed. That’s the 11 claims our map shows. It also listed 224 Closed claims, 185 lode and 39 placer, the same as our map. The quarter counts can add up to more than the number of claims, because one claim can reach into two quarters, and the same claim may show on more than one line of the report.
What this tells a prospector: this section has been staked and dropped over and over, and someone staked a new placer claim there as recently as April 2026. The northeast quarter is where the active placer claims are, so that’s the part to stay out of without permission. If MLRS shows something different from our map, trust MLRS, since claims open and close all the time.
Reading a claim’s record
The Serial Register Page shows the claim name, the claim type, the claimant, the date it was staked, its case disposition (active or closed) and its filing history. You may also see BLM’s number codes for claim types: 384101 is a lode claim, 384201 is a placer claim, 384301 is a tunnel site and 384401 is a mill site.
Every claim recorded with BLM gets a serial number. Claims filed in MLRS get a two-letter code for the BLM state office followed by a nine-digit number. In Montana, for example, BLM says claims carry a nine-digit number starting with “MT,” or an older number of six or fewer digits starting with “MMC.”
Those older numbers are called legacy serial numbers, and BLM kept them searchable. If a seller, a county record or an old map gives you a legacy number, MLRS can still find it.
Active vs. closed claims
An active claim is one the owner is keeping up. Stay off active claims unless you have the owner’s permission, since the minerals there belong to the claim holder.
A closed claim is one that was dropped, most often because the owner didn’t pay the yearly maintenance fee or file a small miner waiver by September 1. Closed ground is often open to prospecting again. Our guide to abandoned gold claims covers what you can and can’t do there.
Keep in mind that a new claim has up to 90 days after it’s staked to be recorded with BLM, so a fresh claim may not show up in MLRS yet. Claims that miss the September 1 deadline can also take a while to show as closed. Watch for claim markers when you get there.
What it costs to keep a claim
The fees explain why so many claims close. Every active claim costs its owner money each year, due on or before September 1:
| Claims held | Yearly BLM maintenance fee |
|---|---|
| 1 lode claim | $200 |
| 10 lode claims | $2,000 |
| 1 placer claim of 20 acres | $200 |
| 1 placer claim of 40 acres | $400 |
| 10 or fewer claims, with a small miner waiver | No fee, but at least $100 of work on each claim and a $15 per claim filing by December 30 |
A brand-new lode claim costs $274 to file with BLM ($25 processing, $49 location and $200 maintenance), plus county recording fees. A new placer claim pays the same $25 and $49 plus $200 for each 20 acres. Source: BLM mining claim fees page.
The fee is a big part of why the number of active claims rises and falls with gold prices. See how each state has changed since 2013 on the mining claims by state page.
Who owns a mining claim?
The public MLRS reports have privacy redactions, so the names and addresses of individual claim owners are often hidden, though business names usually still show. Since companies hold about 90% of active claims, you’ll usually see a company name. BLM’s reports page links to instructions for signing in with a Login.gov account if you need to see the unredacted reports.
You can also contact the BLM state office public room, which keeps the official case files, or the county recorder’s office where the claim was recorded. Those files hold the certificate of location and the claim map.
MLRS won’t show you a claim’s exact boundaries. BLM says the exact location is found by the claim markers on the ground, and the claim map in the case file helps you find them.
BLM’s mining claims map
MLRS also has a Research Map at mlrs.blm.gov/s/research-map. It shows cases on a map, and you can search by serial number or legal land description and open a claim’s record from there. Some features need you to sign in. BLM notes that claim locations are mostly shown down to the quarter section, not the exact claim outline, because that’s all claimants are required to file.
For quick field checks, many people find the Geographic Report easier, since you only need the MTRS code. The Research Map also needs a good connection, which you often won’t have out where the gold is.
Using the code from our map popups
Our maps are built to make that lookup easy. When you click a section on one of our maps, the popup shows the number of active claims (including how many are in each quarter), the date the newest claim was staked, the number of closed claims, the county, and the township, range and section. It also shows the code in the exact format MLRS wants, like “BLM code (MTRS): 14 0090N 0020E 008,” and a “Check before you go: BLM MLRS reports” link.
Every state map has these popups, from our Nevada mining claims map to the California mining claims map. Copy the code, click the link, open the Geographic Report, paste the code into the “Meridian Township Range Section” box and tick Active and Filed under Case Disposition. If MLRS shows a claim that wasn’t there when our data was built, trust MLRS.
The maps use October 2026 claim data in five layers (active lode, active placer, abandoned lode, abandoned placer, and old mines and prospects), and they work in Google Earth and in Organic Maps for offline use, so you can see the claim picture even with no signal. They’re a guide to where to look, not legal proof of who holds a claim, so the BLM record is always the final word. If you’re new to the maps, start with how to open your gold map, and when you find open ground, our guides on how to pan for gold and where to find gold can help with the next step.