Section 179 & Bonus Depreciation for CNC Machine Financing

If you run a job shop or precision machining business, a new CNC lathe or 5-axis mill can run from $85,000 to well past $200,000. The good news for 2025 and 2026 is that the federal tax code lets you deduct a large share of that cost in the first year — even when you finance the machine and have only made a few payments. Used correctly, Section 179 and bonus depreciation can turn a six-figure purchase into a meaningfully smaller after-tax outlay. This guide walks through how the deduction works for financed equipment, the current limits after the 2025 law changes, and how the two provisions interact with your loan.

How Section 179 works for a CNC machine

Normally, when you buy a capital asset like a CNC machine, you depreciate its cost over several years (CNC machining equipment typically falls under a 7-year MACRS class life). Section 179 of the Internal Revenue Code lets you skip that schedule and deduct the full purchase price in the year you place the machine in service, instead of spreading it out.

The machine must be used more than 50% for business, and the deduction can't exceed your taxable business income — Section 179 can't create or deepen a loss (any excess carries forward). Both new and used CNC equipment qualify, which matters in a market where reconditioned lathes and mills hold strong value.

The key for shops buying on credit: the deduction is based on when the equipment is placed in service, not on how much you've paid. If you take delivery and commission the machine in December, you can generally claim the full Section 179 deduction for that tax year even if your first loan payment hasn't cleared yet.

Current limits: the 2025 OBBBA changes

The One Big Beautiful Bill Act (OBBBA), enacted in 2025, sharply raised the Section 179 ceilings. For tax years beginning in 2025, per the IRS instructions for Form 4562, the figures are:

• Maximum Section 179 deduction: $2,500,000 (IRS Instructions for Form 4562).
• Phase-out (investment) threshold: $4,000,000 — the maximum deduction is reduced dollar-for-dollar by the amount your total Section 179 property placed in service exceeds $4,000,000 (IRS Instructions for Form 4562).
• Complete phase-out at $6,500,000 of qualifying purchases (Section 179 deduction guidance, OBBBA summary).

That's roughly double the prior $1,250,000 cap and $3,130,000 threshold. For the overwhelming majority of machine shops — where a single machine or even a full cell costs far less than $4 million — the phase-out is irrelevant, and the entire cost of your CNC purchase will sit comfortably under the deduction limit.

As of this review on 01/06/2026, these are the figures published by the IRS for tax years beginning in 2025. Limits are indexed and can change year to year — confirm the current-year numbers with a tax professional before filing.

Bonus depreciation: the 100% restoration

Bonus depreciation is the second lever. The OBBBA permanently restored 100% bonus depreciation for qualified property both acquired and placed in service after 19/01/2025 (Grant Thornton: OBBBA depreciation alert). This reversed the TCJA phase-down that had cut bonus depreciation to 40% for 2025 and was set to eliminate it by 2027.

Qualifying property is tangible property with a recovery period of 20 years or less — which covers CNC machine tools, including used equipment, as long as it's new to your business (RSM: OBBBA restores and expands bonus depreciation).

Watch the dates: to get 100% bonus, both the acquisition date and the placed-in-service date must fall after 19/01/2025. A machine you contracted to buy before that date can default to the old 40% TCJA bonus rate even if delivered later (DHJJ: OBBBA bonus depreciation & Section 179 2025).

Section 179 vs. bonus depreciation

They overlap, and most shops use them together:

• Section 179 is elective and applied asset-by-asset, capped at $2,500,000, limited to business income, and phases out above $4,000,000 of purchases.
• Bonus depreciation is automatic (you can elect out), has no dollar cap, and can create a taxable loss.

The common ordering is to apply Section 179 first to specific assets, then bonus depreciation to whatever's left. With 100% bonus back, many machine shops can write off the entire cost of a CNC purchase in year one through bonus alone — though Section 179 still offers more control when you want to fine-tune which assets and how much you deduct.

How financing interacts with the deduction

This is where buying a CNC machine on credit becomes genuinely powerful. Because the deduction is tied to placing the equipment in service rather than to cash paid, a financed machine can produce a first-year deduction that exceeds your out-of-pocket payments for the year.

Consider a $120,000 5-axis mill financed over 60 months. In the year you commission it, you might deduct the full $120,000 under Section 179 or bonus depreciation, while having paid only a few monthly installments. The tax savings — at, say, a 21% federal rate that's roughly $25,000 — can offset a large slice of that first year's payments. You're effectively using the IRS to subsidize the down payment on your loan.

A few honest caveats:

• A true lease is different. If you operate-lease the machine rather than finance-to-own it, you typically deduct the lease payments as expenses instead of claiming Section 179 — the tax math flips. Capital/finance leases that transfer ownership generally do qualify. Weigh this carefully when you compare structures in our CNC lease vs. buy guide.
• Recapture risk. If you sell or stop using the machine for business before its depreciation period ends, the IRS can recapture (claw back) part of the deduction as ordinary income.
• The deduction reduces, not eliminates, cost. A $120,000 machine still costs you the loan principal plus interest; Section 179 lowers the after-tax price, it doesn't make the machine free.

Before you let a tax benefit drive a purchase, make sure the machine pays for itself on utilization — the affordability math matters as much as the deduction, and you can sanity-check the monthly numbers with our CNC affordability calculator.

Bottom line

For 2025 and 2026, the combination of a $2,500,000 Section 179 cap and restored 100% bonus depreciation means most financed CNC purchases can be deducted in full the year they hit your shop floor — often producing tax savings larger than that year's loan payments. The rules are favorable but date- and structure-sensitive, and tax outcomes depend on your entity, income, and state conformity. Treat this article as a starting point, not advice: confirm the current-year limits and your specific situation with a qualified tax professional before you file.