Self-Employed Blacksmith Tax Deductions (2026): The Detached-Forge Rule That Doesn't Automatically Cover Your Mileage

Published: September 15, 2026 · Reading time: 13 min

TL;DR: A backyard forge is almost always deductible on its own — a separate structure not attached to the dwelling, used regularly and exclusively for the business, qualifies under IRC §280A(c)(1)(C) without needing to be your "principal place of business." Whether your drive to a fair or install is deductible mileage turns on a different, three-part rule from Rev. Rul. 99-7: a temporary booking outside your metro area converts regardless of anything else, a temporary booking anywhere converts if you already have a regular away-from-home work location, and only a temporary booking close to home with no other regular location falls back to whether the forge desk also satisfies §280A(c)(1)(A) — the administrative-activities test. Layer on Cost of Goods Sold for a business that sells both custom commissions and ready-made fair inventory (same COGS mechanics either way, simplified for small sellers under §471(c)), equipment that's not listed property under §280F(d)(4)(A) but splits between the $2,500 de minimis safe harbor and 100% bonus depreciation, and a QBI deduction where blacksmithing clears the SSTB test easily but still runs into the 20%-of-taxable-income cap.

Blacksmithing looks like the most analog trade on this site — fire, iron, a hammer — and it still runs almost entirely on Schedule C mechanics that trip up freelancers in far more modern businesses: a home workspace test with three different doors in, a product business that has to compute Cost of Goods Sold, and equipment purchases that split across two different expensing rules depending on price. Get the forge/mileage distinction wrong and you're either underclaiming a deduction you're entitled to or overclaiming one you're not — and an IRS notice doesn't care which direction the error ran.

The Trade in One Sentence

You forge and sell metal goods — hardware, railings, gates, tools, and blades — some made to a specific customer's commission, some carried as finished stock to sell at craft fairs and maker markets. Income arrives two ways: custom-commission deposits and balances paid directly by clients, and cash/card sales at fair booths, both of which are Schedule C gross receipts regardless of channel.

Two Different Doors Into §280A — And Only One of Them Reaches Your Mileage

IRC §280A generally disallows a deduction for business use of a home, then carves exceptions back in. The exception that matters most for a shop-based artisan is:

"(c) Exceptions for certain business or rental use... (1) Certain business use. Subsection (a) shall not apply to any item to the extent such item is allocable to a portion of the dwelling unit which is exclusively used on a regular basis— (A) as the principal place of business for any trade or business of the taxpayer, (B) as a place of business which is used by patients, clients, or customers in meeting or dealing with the taxpayer in the normal course of his trade or business, or (C) in the case of a separate structure which is not attached to the dwelling unit, in connection with the taxpayer's trade or business."

Three doors, and they're independent — you only need to satisfy one. For a converted garage or backyard shed used as a forge, (C) is usually the easiest: it doesn't require the space to be your "principal place of business," doesn't require client meetings, and doesn't require you to do anything administrative there at all. If the building is a genuinely separate structure and you use it regularly and exclusively for the metalworking side of the business, the utilities, insurance, and depreciation allocable to it are deductible.

Where the Assumption Breaks

It's natural to assume that a deductible workshop means the drive there and back is deductible too. It isn't automatic, and the rule that actually governs mileage is a different one. Rev. Rul. 99-7 doesn't give you just one route to a deductible commute — it lays out three, and only one of them touches §280A at all:

"(1) A taxpayer may deduct daily transportation expenses incurred in going between the taxpayer's residence and a temporary work location outside the metropolitan area where the taxpayer lives and normally works. … (2) If a taxpayer has one or more regular work locations away from the taxpayer's residence, the taxpayer may deduct daily transportation expenses incurred in going between the taxpayer's residence and a temporary work location in the same trade or business, regardless of the distance. … (3) If a taxpayer's residence is the taxpayer's principal place of business within the meaning of § 280A(c)(1)(A) … the taxpayer may deduct daily transportation expenses incurred in going between the residence and another work location in the same trade or business, regardless of whether the other work location is regular or temporary and regardless of distance."

"Temporary" here means work that's realistically expected to last — and does last — a year or less. A weekend craft fair or a one-off install is the paradigm case. So a forge that's deductible purely because it's a detached structure "in connection with" the trade (C) doesn't, by itself, convert a drive to a regular, recurring nearby booking — but it doesn't need to, for a temporary one: holding (1) reaches a temporary location outside your metro area with no home-office qualification of any kind, and holding (2) reaches a temporary location at any distance once you have some other regular away-from-home work location. Only a temporary booking close to home, with no other regular work location to lean on, is left needing holding (3) — the forge desk itself satisfying (A).

The Fix Is Usually Free — If You Actually Use It

Even for that narrower case, the good news is most solo blacksmiths already have the fact pattern to clear (A) too. §280A(c)(1)'s flush language defines "principal place of business" to include a location used for the trade's administrative or management activities — scheduling commissions, invoicing, bookkeeping, ordering steel — if there is no other fixed location where you conduct substantial administrative or management activities for the business. Nothing in the statute says this has to happen in a different room from the forge itself, and occasional work from a laptop at a coffee shop, in a car, or in a hotel room doesn't count against you — IRS Publication 587 says exactly that: those aren't "fixed locations" of the business at all. If your invoicing desk sits in the same detached building where you swing a hammer, and you have no other fixed location where you handle a substantial share of that work, the building satisfies both (A) and (C).

Where it breaks down: a blacksmith who also keeps a small studio downtown for consulting on architectural ironwork projects has a genuine second fixed location for administrative work — that knocks the home forge out of (A) even though it's still solidly inside (C). The forge keeps its own deduction; whether the mileage converts then depends on which of the three holdings above the trip actually fits.

node -e "
const scenarios = [
  { name: 'Forge doubles as admin desk', forgeDeductible: true, outOfMetroFairMileage: true, nearbyTempInstallMileage: true },
  { name: 'Forge only, substantial admin done at a second studio', forgeDeductible: true, outOfMetroFairMileage: true, nearbyTempInstallMileage: false },
];
for (const s of scenarios) {
  console.log(s.name, '-> forge:', s.forgeDeductible, '| out-of-metro fair (holding 1):', s.outOfMetroFairMileage, '| nearby temp install, no other regular location (holding 3 / (A)):', s.nearbyTempInstallMileage);
}
"

Forge doubles as admin desk -> forge: true | out-of-metro fair (holding 1): true | nearby temp install, no other regular location (holding 3 / (A)): true
Forge only, substantial admin done at a second studio -> forge: true | out-of-metro fair (holding 1): true | nearby temp install, no other regular location (holding 3 / (A)): false

Worth noting too: §280A(c)(2) has a separate, lower-bar exception for storing inventory or product samples in the dwelling itself — no exclusive-use requirement — but only "if the dwelling unit is the sole fixed location of such trade or business." A forge in a detached structure doesn't disqualify you from also using a hall closet to store finished stock under this rule, but it does mean you have two different provisions doing two different jobs, not one blanket "home business" exception.

The 2026 Mileage Rate — Split at July 1

2026 has two rates, confirmed directly against the IRS's own standard mileage page: $0.725/mile from January 1 through June 30, 2026, and $0.76/mile from July 1 through December 31, 2026. A blacksmith whose circuit runs spring art fairs before the split and holiday markets after it needs both halves logged separately, not averaged.

A worked year — 3 spring fair round trips (140 mi each) and 4 spring install visits (35 mi each) before July 1; 5 holiday fair round trips (160 mi each) and 6 fall install visits (30 mi each) after:

node -e "
const h1Miles = 3*140 + 4*35;
const h2Miles = 5*160 + 6*30;
const h1Rate = 0.725, h2Rate = 0.76;
const h1Deduction = h1Miles*h1Rate;
const h2Deduction = h2Miles*h2Rate;
console.log('H1 miles', h1Miles, '-> $'+h1Deduction.toFixed(2));
console.log('H2 miles', h2Miles, '-> $'+h2Deduction.toFixed(2));
console.log('total miles', h1Miles+h2Miles);
console.log('total mileage deduction', (h1Deduction+h2Deduction).toFixed(2));
"

H1 miles 560 -> $406.00
H2 miles 980 -> $744.80
total miles 1540
total mileage deduction 1150.80

Not all of that $1,150.80 rides on the same test. The fair round trips (140–160 miles round trip — comfortably outside a typical metro area) are temporary, out-of-metro bookings, so they convert under Rev. Rul. 99-7's holding (1) regardless of whether the forge desk satisfies §280A(c)(1)(A):

node -e "
const h1FairMiles = 3*140, h2FairMiles = 5*160;
const h1InstallMiles = 4*35, h2InstallMiles = 6*30;
const h1Rate = 0.725, h2Rate = 0.76;
const fairDeduction = h1FairMiles*h1Rate + h2FairMiles*h2Rate;
const installDeduction = h1InstallMiles*h1Rate + h2InstallMiles*h2Rate;
console.log('fair miles (out-of-metro, holding 1)', h1FairMiles+h2FairMiles, '-> $'+fairDeduction.toFixed(2));
console.log('install-visit miles (nearby, depends on (A))', h1InstallMiles+h2InstallMiles, '-> $'+installDeduction.toFixed(2));
console.log('sum', (fairDeduction+installDeduction).toFixed(2));
"

fair miles (out-of-metro, holding 1) 1220 -> $912.50
install-visit miles (nearby, depends on (A)) 320 -> $238.30
sum 1150.80

Only the $238.30 of nearby install-visit mileage actually depends on the forge desk satisfying (A) as worked through above — assuming those installs are one-off jobs and there's no other regular away-from-home work location to invoke holding (2) instead. If the forge desk fails (A), that $238.30 drops to $0; the $912.50 of out-of-metro fair mileage is unaffected either way.

Cost of Goods Sold: Custom Commissions and Fair Inventory, Same Mechanics

The single biggest structural difference between a blacksmith and most other trades covered on this site: you're selling tangible personal property, which means Schedule C Part III (Lines 33–42) applies, not just Part II operating expenses. Whether a piece was made to a customer's exact commission or pulled off your fair table doesn't matter for COGS — the direct materials cost is COGS either way. Line 37's "cost of labor" is production labor that goes into making the goods (a shop hand at the forge, say) — a helper who works the sales side at a fair booth is a selling expense, not COGS, and belongs in Part II as contract labor instead.

A second-year blacksmith carrying inventory forward from last year:

node -e "
const beginInv = 1800, purchases = 10400, materials = 1250, otherCosts = 310;
const line40 = beginInv + purchases + materials + otherCosts;
const endInv = 2400;
const cogs = line40 - endInv;
console.log('Line 40', line40.toFixed(2));
console.log('Line 42 (COGS)', cogs.toFixed(2));
"

Line 40 13760.00
Line 42 (COGS) 11360.00

Under IRC §471(c), a small-business taxpayer — average gross receipts at or below the §448(c) threshold ($32 million for 2026), which covers essentially every solo maker — can treat inventory as non-incidental materials and supplies and deduct cost when items sell, rather than running a formal periodic count-and-value process. You still report the Line 42 figure; §471(c) just simplifies how you get there. See the corpus's Schedule C Part III guide for the full line-by-line mechanics and the no-double-dip rule against claiming the same raw material as both COGS and a Part II supply.

Equipment: Not Listed Property, But It Splits on Price

The anvil, power hammer, forge unit, tongs, and hardy tools have no consumer entertainment or recreational use and aren't transportation, so none of it is listed property under IRC §280F(d)(4)(A), which covers passenger vehicles, other transportation property, property "of a type generally used for purposes of entertainment, recreation, or amusement," and anything else added by Treasury regulation — no such regulation reaches ordinary shop tools. No heightened business-use-percentage substantiation applies.

What actually separates how each item is expensed is the $2,500 de minimis safe harbor threshold, not listed-property status:

Bonus depreciation under IRC §168(k) was permanently restored to 100% by the One Big Beautiful Bill Act for property acquired after January 19, 2025 (and placed in service in the year claimed) — so a power hammer and a forge unit bought and placed in service in 2026 can generally both be written off in full the year they're bought, the same as the smaller tools expensed through the de minimis election. See the corpus's de minimis safe harbor guide and Section 179 guide for the mechanics of each election.

The Rest of the Deduction List

If you also haul steel and booth equipment in a heavy pickup, the vehicle-specific depreciation caps and GVWR mechanics are worked through in the corpus's heavy-vehicle Section 179 guide — this post keeps its equipment focus on the forge and tools rather than duplicating that analysis.

A Full Year, Worked

Single filer, no other income, standard deduction only, forge desk satisfies both §280A(c)(1)(A) and (C):

node -e "
const grossReceipts = 72000, cogs = 11360;
const grossProfit = grossReceipts - cogs;
const opEx = {
  mileage: 1150.80, boothFees: 1200, propaneElectric: 2600, structureInsurance: 600,
  equipmentBonus: 6500 + 2800, deMinimisTools: 2100, boothHelperContractLabor: 900,
  liabilityInsurance: 950, abanaTraining: 850, licenses: 220, website: 300, advertising: 500, phone: 300,
};
let totalOpEx = 0;
for (const k in opEx) totalOpEx += opEx[k];
const netProfit = grossProfit - totalOpEx;
console.log('grossProfit', grossProfit.toFixed(2));
console.log('totalOpEx', totalOpEx.toFixed(2));
console.log('netProfit', netProfit.toFixed(2));
"

grossProfit 60640.00
totalOpEx 20970.80
netProfit 39669.20

Self-employment tax

node -e "
const netProfit = 39669.20;
const netSE = netProfit * 0.9235;
const seTax = netSE * 0.153;
const halfSE = seTax / 2;
console.log('net SE earnings (92.35% of profit)', netSE.toFixed(2));
console.log('SE tax (15.3%)', seTax.toFixed(2));
console.log('deductible half', halfSE.toFixed(2));
"

net SE earnings (92.35% of profit) 36634.51
SE tax (15.3%) 5605.08
deductible half 2802.54

Well under the $184,500 Social Security wage base for 2026 (confirmed directly against the Social Security Administration's 2026 cost-of-living notice), so the full 12.4% applies with no cap this year.

QBI deduction — checking every limit that could plausibly bind

Blacksmithing clears the SSTB test easily — it isn't in §199A(d)(2)'s list. §199A separately caps the deduction at the lesser of 20% of QBI or 20% of taxable income (computed without regard to the QBI deduction itself, per §199A(e)(1)) minus net capital gain. A third limit — the W-2 wage / 2.5%-of-property cap — only starts phasing in once taxable income clears $201,750 for a single filer in 2026 (confirmed against Rev. Proc. 2025-32), so it's worth checking whether this example even gets close before assuming it doesn't matter:

node -e "
const netProfit = 39669.20;
const halfSE = 2802.54;
const qbiBaseline = netProfit - halfSE;
const qbi20 = qbiBaseline * 0.20;

const AGI = netProfit - halfSE; // no other above-the-line adjustments in this example
const stdDeduction = 16100; // 2026 single filer, per Rev. Proc. 2025-32 (IRB 2025-45)
const taxableIncomeForCap = AGI - stdDeduction; // before the QBI deduction itself, per §199A(e)(1)
const cap20 = taxableIncomeForCap * 0.20;

const qbiDeduction = Math.min(qbi20, cap20);
const wagePropertyThreshold2026Single = 201750;

console.log('QBI baseline', qbiBaseline.toFixed(2));
console.log('20% of QBI', qbi20.toFixed(2));
console.log('taxable income before QBI deduction', taxableIncomeForCap.toFixed(2));
console.log('20% of taxable income (the cap)', cap20.toFixed(2));
console.log('QBI deduction (lower of the two)', qbiDeduction.toFixed(2));
console.log('amount the cap cost vs. the uncapped 20% x QBI figure', (qbi20 - cap20).toFixed(2));
console.log('taxable income vs. 2026 wage/property cap threshold', taxableIncomeForCap.toFixed(2), '<', wagePropertyThreshold2026Single, '=>', taxableIncomeForCap < wagePropertyThreshold2026Single);
"

QBI baseline 36866.66
20% of QBI 7373.33
taxable income before QBI deduction 20766.66
20% of taxable income (the cap) 4153.33
QBI deduction (lower of the two) 4153.33
amount the cap cost vs. the uncapped 20% x QBI figure 3220.00
taxable income vs. 2026 wage/property cap threshold 20766.66 < 201750 => true

Three limits, three separate checks: not an SSTB, so no phase-out; taxable income of $20,766.66 is nowhere near the $201,750 threshold where the W-2 wage/property cap would even start to phase in, so that cap doesn't bind either; but the 20%-of-taxable-income cap does — it produces $4,153.33 against a naive $7,373.33 from simply taking 20% of QBI, a $3,220.00 overstatement if only the SSTB question had been checked.

Common Mistakes to Avoid

• Assuming a deductible forge means deductible mileage — or the reverse. §280A(c)(1)(C) and §280A(c)(1)(A) are independent tests, but Rev. Rul. 99-7 doesn't route every trip through (A) either. A temporary booking outside your metro area, or anywhere once you have another regular work location, converts on its own; only a nearby, no-other-location booking depends on the forge desk also satisfying (A).
• Skipping Part III because "it's mostly custom work." Custom or ready-made doesn't change whether materials that become part of a sold piece are Cost of Goods Sold. Both channels feed the same Line 42.
• Treating the power hammer like the anvil. The $2,500 de minimis threshold, not listed-property status, is what separates an immediate Line 22 write-off from a Line 13 depreciation election.
• Assuming your home state's sales-tax rules travel with you to an out-of-state fair. Physical presence at a booth is its own nexus trigger, state by state.
• Stopping the QBI analysis at "I'm not an SSTB." That clears only the SSTB phase-out. The taxable-income cap — and, at higher income, the W-2 wage/property cap — are separate, independent tests.
• Deducting a beginning inventory figure that doesn't match last year's ending inventory. Line 35 must equal last year's Line 41; a mismatch with no explanation is a flag.

Frequently Asked Questions

Is blacksmithing a Specified Service Trade or Business (SSTB) for QBI purposes?

No. §199A(d)(2)(A) defines the SSTB category by cross-reference to §1202(e)(3)(A) — health, law, accounting, actuarial science, performing arts, consulting, athletics, financial services, brokerage services, and reputation-or-skill businesses (engineering and architecture are named there but carved back out for §199A purposes). Making and selling forged goods is a manufacturing and craft trade, not any of those fields. Non-SSTB means no SSTB phase-out — it does not mean the deduction is uncapped, since the separate 20%-of-taxable-income limit under §199A(a)(2) applies to every business regardless.

If my detached forge building qualifies for the home-workshop deduction, does that also make my drives to craft fairs deductible?

Not automatically. §280A(c)(1)(C) — a separate structure used in connection with the business — makes the forge's own utilities, insurance, and depreciation deductible on its own, low-bar terms. Whether the drive itself converts depends on Rev. Rul. 99-7's three independent holdings: a temporary booking outside your metro area converts regardless of your home office; a temporary booking anywhere converts once you have some other regular away-from-home work location; and only a temporary booking close to home, with no other regular location, falls back to whether that same forge desk also satisfies §280A(c)(1)(A) — meaning you do your invoicing and bookkeeping there with no other fixed location for substantial admin work. If it doesn't, the forge deduction stands alone and that narrower category of trip stays commuting — most out-of-town fairs convert either way.

Do I need to track formal inventory if I sell both custom commissions and ready-made pieces at craft fairs?

Usually not in the formal sense, but you complete Schedule C Part III either way — COGS doesn't distinguish custom work from ready stock, only whether materials became part of something sold. Under §471(c), a small-business taxpayer (average gross receipts at or below the $32 million §448(c) threshold for 2026 — effectively every solo blacksmith) can treat inventory as non-incidental materials and supplies and deduct cost when sold, skipping a formal year-end valuation. You still report the resulting COGS figure on Line 42.

Are my anvil, power hammer, and forge "listed property" that needs special records?

No. §280F(d)(4)(A) listed property covers passenger vehicles, other transportation property, and property of a type generally used for entertainment, recreation, or amusement — none of which describes blacksmithing equipment. What matters instead is the $2,500 de minimis safe harbor threshold: items at or under that per-item cost (an anvil, tongs, hardy tools) go straight to Line 22 as supplies; larger single purchases like a power hammer or forge unit are expensed through Section 179 or 100% bonus depreciation on Line 13, though ordinary business-use records still apply either way.

Do I owe sales tax when I sell at an out-of-state craft fair?

Almost always, yes. Physical presence at a fair booth is a well-established, independent trigger for state sales-tax nexus in most states, separate from any revenue-based economic-nexus threshold. Most states require a temporary seller's permit for a single event or short circuit; some fair organizers collect and remit under a marketplace-facilitator arrangement instead, so confirm with each event rather than assuming your home state's rules travel with you.

Does the taxable-income cap on QBI apply even though blacksmithing isn't an SSTB?

Yes, and it's frequently the limit that actually binds. §199A caps the deduction at the lesser of 20% of qualified business income or 20% of taxable income (computed without regard to the QBI deduction itself) minus net capital gain, and that second cap applies to every qualifying business regardless of SSTB status. A maker business with real material costs — steel, coal, hardware — routinely lands with taxable income well below its QBI base once the standard deduction and half-SE-tax adjustment come off, which is exactly when the taxable-income cap, not the SSTB question, decides the final number.

Authoritative References

• IRC §280A — Disallowance of certain expenses in connection with business use of home
• Rev. Rul. 99-7, 1999-1 C.B. 361 (IRS Internal Revenue Bulletin 1999-5)
• IRC §280F(d)(4) — Definition of listed property
• IRC §199A — Qualified Business Income
• IRC §1202(e)(3) — Qualified trade or business, SSTB list
• IRC §471(c) / §448(c) — Small-business inventory exemption
• IRC §168(k) — Bonus depreciation
• IRS — Standard mileage rates
• IRS Publication 587 — Business Use of Your Home

Related reading: Schedule C Part III — Cost of Goods Sold · QBI deduction for freelancers · De minimis safe harbor election · Bonus depreciation for freelancers · Sales tax for freelancers · Self-employment tax explained

Every Commission, Every Fair, One Set of Books

Between a home structure with three different qualifying tests and a business that has to compute Cost of Goods Sold on top of ordinary Schedule C expenses, a blacksmith's books have more moving parts than most one-person trades. CentSense scans every steel, coal, and hardware receipt with AI and tags it to Cost of Goods Sold or supplies as it comes in, logs mileage at the correct 2026 half-year rate, and exports a CPA-ready CSV at year end so nothing gets reconstructed from memory in April. Free tier includes 10 AI receipt scans a month, no credit card required; the Solo plan ($5/month) adds unlimited scans, mileage tracking, and the export.

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This article is educational and not tax or financial advice. Consult a qualified tax professional about your specific situation.