What is the Section 179 limit for 2026?

$2,560,000, with the phase-out beginning at $4,090,000 of qualifying purchases, per Revenue Procedure 2025-32. For tax years beginning in 2025 the limit is $2,500,000 with a $4,000,000 phase-out.

Is bonus depreciation 100% again?

Yes, for qualified property acquired after January 19, 2025, and it was made permanent rather than phased down.

Is a modular office 7-year property?

The modular building industry's position is that relocatable modular buildings can often qualify for 5- or 7-year treatment as tangible personal property. That is not an IRS ruling. Confirm with your tax professional.

Does installation count?

Installation costs are generally part of the asset's basis. Keep the equipment, freight, and installation lines separate on the invoice so your CPA can treat them correctly.

Compliance · Plant-wide

Can you expense a modular office or a mezzanine in the year you buy it?

Reviewed September 25, 2026. Official sources are linked where they exist.

Short answer

For tax years beginning in 2025 the maximum Section 179 deduction is $2,500,000, reduced dollar for dollar once purchases exceed $4,000,000; for 2026 the inflation-adjusted figures are $2,560,000 and $4,090,000. Separately, the 2025 tax law made 100% first-year bonus depreciation permanent for qualified property acquired after January 19, 2025. Whether a modular office or a bolted, relocatable mezzanine qualifies as tangible personal property rather than a building improvement is the question that decides the treatment. The modular building industry's position is that relocatable buildings typically qualify and can often be treated as 5- or 7-year property; that is an industry position, not an IRS ruling, so confirm it with your tax professional before you book it.

The numbers, from the IRS

These are the figures a controller needs. The 2025 limits are from IRS Publication 946; the 2026 figures are the inflation adjustments in Revenue Procedure 2025-32.

Section 179 and bonus depreciation
Section 179 maximum, tax years beginning in 2025	$2,500,000, phased out above $4,000,000 of purchases
Section 179 maximum, tax years beginning in 2026	$2,560,000, phased out above $4,090,000 of purchases
Bonus (special) depreciation	100% for qualified property acquired after January 19, 2025, made permanent by Public Law 119-21
7-year MACRS property, examples	Office furniture and fixtures, per Publication 946

Why the classification matters

Section 179 and bonus depreciation apply to tangible personal property and certain improvements; a permanent building improvement is depreciated over 39 years. A modular office that is bolted to the slab, demountable, and relocatable, and a free-standing work platform that is bolted down rather than built into the structure, are the kinds of assets the industry treats as equipment. The Modular Building Institute states that relocatable modular buildings typically meet the criteria for tangible personal property and can often qualify for 5- or 7-year MACRS treatment, while advising readers to consult a qualified tax professional.

What we can do on our side is make the equipment case easy to document: line-item quotes that show the building or platform as a demountable, bolted assembly with installation as a separate line, drawings that show anchor points rather than foundations, and the freight and installation invoices kept separate from the equipment.

This page is not tax advice

We sell equipment. Your CPA decides how you depreciate it, and the answer depends on how the asset is attached, how it is used, and the rest of your return. Bring the quote and the drawings to that conversation.

Questions buyers ask

What is the Section 179 limit for 2026?: $2,560,000, with the phase-out beginning at $4,090,000 of qualifying purchases, per Revenue Procedure 2025-32. For tax years beginning in 2025 the limit is $2,500,000 with a $4,000,000 phase-out.
Is bonus depreciation 100% again?: Yes, for qualified property acquired after January 19, 2025, and it was made permanent rather than phased down.
Is a modular office 7-year property?: The modular building industry's position is that relocatable modular buildings can often qualify for 5- or 7-year treatment as tangible personal property. That is not an IRS ruling. Confirm with your tax professional.
Does installation count?: Installation costs are generally part of the asset's basis. Keep the equipment, freight, and installation lines separate on the invoice so your CPA can treat them correctly.

Do your own research

Official sources first. We link the rule, not a summary of the rule, wherever one exists.

Publication 946, How To Depreciate Property
Internal Revenue Service
Section 179 limits for 2025, 7-year property classes, and the special depreciation allowance.
Treasury, IRS issue guidance on the additional first year depreciation deduction (IR-2026-06)
Internal Revenue Service
Permanent 100% bonus depreciation for property acquired after January 19, 2025.
Revenue Procedure 2025-32
Internal Revenue Service
2026 inflation adjustments including the Section 179 limits.
New tax rules allow 100% first-year expensing for modular buildings
Modular Building Institute
The industry's position on relocatable buildings as tangible personal property. Not an IRS ruling.

What we quote for this

Modular Offices

Modular In-Plant Office, Standard Sizes

Pre-engineered single-room offices from 8' x 8' to 20' x 20', with two-story and mezzanine-mounted options.

Size: 8' x 8' through 20' x 20' standard; custom on request
Wall height: 8' standard
Wall system: Pre-finished panels on a post frame; steel or vinyl-covered gypsum faces

MO-STDView & quote

Mezzanines

Structural Steel Mezzanine, Engineered to Your Footprint

Free-standing platform engineered to your length, width, clear height, and load, with stairs, handrail, and gates.

Footprint: Sized to your floor; typical 10' x 20' through 40' x 80'
Live load: 125 psf standard; 150 to 250 psf on request
Clear height under deck: Specified per site, typically 8' to 12'

MZ-STDView & quote