Owner Questions
How Many Net Mineral Acres Do I Own?
Multiply the gross acres of the tract by your undivided fractional mineral interest. If you do not know the fraction, it can be reconstructed from the recorded deeds in the county where the minerals sit, or worked backward from the royalty decimal on your check stub.
This is the most common question we get, and it is answerable with public records. The arithmetic is simple; finding the inputs is the work.
The formula
Gross acres in the tract × your undivided fractional mineral interest = your net mineral acres.
An undivided 1/8 interest in a 320-acre tract is 40 net mineral acres. Four heirs splitting that equally hold 10 each. The tract stays 320 acres throughout.
Path A: from the deeds
This is the authoritative route.
- Identify the county and the legal description. Not a street address — a survey, section, block, abstract, or quarter-call. Old check stubs, tax notices, division orders, and lease copies all carry it.
- Find the severance. The first instrument that separated minerals from surface establishes the original fraction. Everything after it can only divide that fraction further.
- Walk forward in order. Each subsequent conveyance or reservation multiplies or subtracts. Keep the arithmetic in fractions rather than decimals to avoid rounding drift.
- Account for deaths. A probated will, deed of distribution, or affidavit of heirship shows how an interest split among heirs. Where nothing was recorded, the interest is still in the deceased person’s name in the record even though the family considers it divided.
- Confirm the tract acreage from the deed or the survey, not from memory. Old descriptions frequently disagree with modern surveys by a few acres.
Path B: from a royalty check
If a well is paying you, work backward from the royalty decimal:
Decimal = (your net acres in the unit ÷ unit gross acres) × royalty rate
So: your net acres = (decimal ÷ royalty rate) × unit gross acres.
You need two facts from outside the stub — the unit’s gross acreage, from the recorded unit designation or the state’s plat, and your royalty rate, from the operative lease or the royalty deed. With a 0.00625 decimal, a 640-acre unit, and a 1/5 royalty: (0.00625 ÷ 0.20) × 640 = 20 net acres.
Two caveats. Only the part of your tract inside the unit counts, so this yields acres in that unit rather than your total holding. And if you hold a fixed-fraction non-participating royalty, the “royalty rate” in the formula is your fixed fraction, not the lease royalty.
Where owners go wrong
- Using surface acreage. The 100-acre myth is the single most common error.
- Assuming an even family split. Wills, life estates, and separate conveyances routinely produce uneven shares — see the subdivision trap.
- Mixing up net mineral acres and net royalty acres. They differ whenever the royalty rate is not 1/8.
- Trusting an offer letter’s acreage. A letter quoting gross acres at an attractive price is often repriced once title is run.
If the paperwork is thin
That is normal, especially for heirs several generations removed. County records are public and the chain can usually be reconstructed from a family name, an approximate date, and a county. We do that research at no cost and will tell you what we find whether or not you ever sell — send us whatever fragments you have, even if it is only a name and a county.
Does owning 100 surface acres mean I own 100 mineral acres?
No. In most producing states the mineral estate can be severed and sold separately from the surface. You may own all the surface and a small fraction of the minerals, or minerals under land you have never owned.
Can I figure out my net acres from my royalty check?
Often yes, approximately. The decimal on the stub equals your net acres in the unit divided by the unit's gross acres, times your royalty rate. With the unit size and royalty rate from the recorded unit designation and lease, you can solve for acreage.
Where are mineral deeds recorded?
In the county (or parish) where the minerals are located, not where the owner lives. That is also where any probate document must be recorded before an operator can pay an heir.
Does a property tax statement show my net mineral acres?
Not reliably. Some states assess producing mineral interests separately and some do not, and the assessed description often does not reflect the fractional arithmetic in the deeds.