Mine License Tax

This is a tax for the privilege of mining or receiving royalties from mining operations in Idaho. The tax rate is 1% of the value of ores mined or extracted and royalties received from mining. This tax has been in effect in Idaho since 1935.

What’s taxable

The following mines are subject to the tax: gold, silver, copper, lead, zinc, coal, phosphate, limestone, and other valuable minerals. Valuable minerals are any substance that makes real property more valuable and for which depletion is allowed under Internal Revenue Code section 613. These include calcium carbonates, garnet, granite, pumice, quartzite, scoria, shale, slate, and stone (including dimension and ornamental stone).

Mining of any substance that’s gaseous or liquid in its natural state isn’t subject to the tax. Sand and gravel mining are also exempt.


Royalties are money or property paid to the owner of the land where the mine is located, in exchange for allowing another party to do the mining. The royalty amount is based on the quantity or value of the minerals extracted.

Use of tax revenue

For most taxpayers, 66% of the revenue collected goes to the state’s general fund and 34% is allocated to the abandoned mine reclamation fund. However, if the taxpayer’s mining operations include a cyanidation facility, then 33% goes to the state’s general fund, 33% to the cyanidation facility closure fund, and 34% to the abandoned mine reclamation fund.


pdf Form 47, Idaho Mine License Tax Return, must be filed by every person, copartnership, company, joint stock company, trust, corporation, or association that mines or receives royalties from any quartz vein or lode, or placer or rock in place mining claim in Idaho that contains precious or valuable minerals or metals. A separate Form 47 must be filed for each mine. However, one Form 47 can be filed for a group of mines that are combined to compute depletion for federal income tax purposes. In most cases the due date for the return is April 15. An automatic extension of time to file a taxpayer’s Idaho income tax return also applies to the taxpayer’s mine license tax return.

Forms and guides

  • Form 47, Idaho Mine License Tax Return (with instructions)

Laws and rules