Michigan Mineral Royalty Calculator: Your Decimal Interest

Step 1: Gather your three inputs

Your net mineral acres in the tract, the unit's spacing acres, and your lease royalty rate — from your deed, your lease, and the EGLE unit record.

Step 2: Compute your decimal

Decimal interest = net mineral acres ÷ unit acres × royalty rate. Use the royalty calculator to check your math.

Step 3: Account for what Michigan takes out

A severance tax of 6.6% on oil and 5% on natural gas of gross value (4% for qualifying stripper wells) is withheld, so your net check is below the gross your decimal implies — plus any post-production deductions your lease allows.

Step 4: Verify against your Michigan division order

The decimal on the division order must match your calculation. If it is low, the operator may have the wrong net acres, unit size, or royalty rate — reconcile it before you sign.

Step 5: Get it audited

Have the decimal and the check history verified. Valor audits Michigan royalties stub by stub as an independent mineral manager.

What is Michigan-specific about your royalty math

The decimal-interest formula does not change by state, but Michigan facts change what you actually receive. Tax: Michigan levies a severance tax of 6.6% on oil and 5% on natural gas of gross value (4% for qualifying stripper wells), withheld before or alongside your royalty, so your net is below the gross your decimal implies. Timing: Michigan law generally requires operators to begin paying proceeds once title is marketable in the owner's name, and to pay on a regular cycle thereafter, and like most producing states, Michigan can impose statutory interest on royalty proceeds held past the period the law allows — confirm the current Michigan rate. Unit size: the acres you divide by depend on how Michigan forms drilling units — the Supervisor of Wells (EGLE) administers compulsory pooling under Part 615 of the Natural Resources and Environmental Protection Act (Mich. Comp. Laws §324.61513; statutory unitization is Part 617), so an unleased Michigan owner can be pooled — which decides whether your tract stands alone or sits inside a larger pooled unit (a bigger denominator, and a smaller decimal on more total production). Verification: spacing and production are regulated by the Michigan Department of Environment, Great Lakes, and Energy (EGLE), Geologic Resources Management Division, whose records confirm the unit acres in your decimal, and your Michigan division order should state a decimal that matches net mineral acres ÷ unit acres × royalty rate. If your Michigan division-order decimal does not match your own calculation, do not sign until it is reconciled; an incorrect decimal underpays you every month it goes uncorrected.

Michigan facts at a glance

The Michigan-specific facts that shape this situation — a citable reference. General guidance as of September 2026; confirm specifics with a CPA or attorney.