NJ Capital Improvement Tax Exemption: What Qualifies and Form ST-8

New Jersey’s capital improvement tax exemption removes the state’s 6.625% sales tax from qualifying home improvement jobs, covering both the contractor’s labor and the materials the contractor supplies, provided you give the contractor a completed Certificate of Exempt Capital Improvement (Form ST-8) before the work is billed.¹ On a mid-sized renovation, that saves a meaningful amount. Getting it right depends on three things: whether your project actually qualifies, whether the paperwork gets to your contractor in time, and whether the work falls into one of the categories New Jersey specifically keeps taxable.

What Counts as a Capital Improvement

A capital improvement is the permanent installation of tangible personal property that either raises the value of the real property or meaningfully extends its useful life.¹ The installed item must be attached so that removing it would cause real damage to either the item or the building.² A new roof qualifies. A central air conditioning system, a paved driveway, an in-ground pool, or a deck all qualify. A ceiling fan you could unbolt in ten minutes does not.

The Division of Taxation’s S&U-2 bulletin runs long example lists. Exempt work includes new construction, kitchen cabinets, bathroom fixtures, storm doors, fencing, rewiring, and a flagpole set in concrete. Taxable work includes repairing gutters, fixing loose bath tiles, patching driveway potholes, and replacing a torn screen.² Repairs restore something to working condition. Improvements make the property more valuable or longer-lasting.

What the Exemption Actually Covers

When the job qualifies and the contractor has your ST-8, the contractor should not collect sales tax from you on any part of the invoice, labor or materials.¹ The contractor still pays sales tax on materials purchased from suppliers, but that cost gets folded into the contract price rather than passed through as a separate tax line.²

Here’s the piece most homeowners miss. If you buy the materials yourself, at a hardware store or supplier, and then hand them to your contractor, you owe sales tax on those materials at the register. The exemption for materials only applies when the contractor purchases and provides them as part of the job.¹ On a $30,000 kitchen remodel, having your contractor supply cabinets and countertops rather than buying them yourself could save close to $2,000 at the 6.625% rate.³

Three Project Types That Stay Taxable

Even when the work is permanent and adds real value, New Jersey specifically excludes three categories from the exemption:

Landscaping services, including planting trees, shrubs, and hedges, sodding or seeding a lawn, and related clearing and filling.
Floor covering installations, including carpeting and other floor coverings installed on top of existing subfloors.
Hard-wired alarm and security systems, including burglar, fire, and security systems permanently attached to the structure.

These three catch people off guard because the work is clearly permanent and clearly adds value. The exclusion is written into the rules separately, so no amount of careful ST-8 preparation makes them exempt.¹ A contractor who accepts an ST-8 for one of these projects is making a mistake, and you will ultimately owe the tax.

Repair or Improvement

The classification decides whether you pay sales tax on the labor. A repair restores property to working condition without adding value or extending its life. A capital improvement does one or both of those things and is permanently attached.²

Some comparisons are easy. Fixing a leaky roof is a repair; replacing the whole roof is an improvement. Others are closer. Replacing a single cracked patio slab is a repair, but repaving the entire driveway is an improvement. Fixing a faulty electrical outlet is a repair, but rewiring the house or adding new outlets is an improvement.² When a job has both, ask the contractor to itemize the charges so the exempt portion is documented clearly.

Filling Out Form ST-8

To claim the exemption, complete Form ST-8, the Certificate of Exempt Capital Improvement, and hand it to your contractor. The form is available from the Division of Taxation’s website.⁴ You need to provide:

Your name and address as the property owner.
Your New Jersey tax identification number. Individuals without one can note “Individual.”
The contractor’s name, address, and New Jersey Certificate of Authority number.
The address where the work will be performed.
A description of the improvement specific enough to show that the work qualifies.

The description matters more than it looks. “Kitchen renovation” is vague enough to invite questions. “Removal and replacement of all kitchen cabinets, countertops, and fixtures” makes the capital-improvement nature of the work plain. You sign under penalty of perjury, so the description has to be accurate.⁵

Get the completed certificate to the contractor before work begins, or at contract signing. If the contractor never receives a valid ST-8, they are legally required to charge sales tax on the full amount of the job, and recovering that afterward is far more work than filling the form out up front.⁵

Keep the Paperwork

The contractor must keep your ST-8 on file for at least three years from the date the contract work is performed.¹ Keep your own copy for at least that long. If the Division of Taxation audits either party, the certificate is the primary proof that the exemption was legitimate.

Filing a false ST-8 carries real consequences. You sign the certificate under penalties for perjury and false swearing.⁵ If an exemption is later found to be improper, the purchaser is responsible for the tax owed plus interest and penalties.⁶ Passing off taxable landscaping work as an exempt capital improvement is the kind of misuse that triggers those provisions.

Verify Your Contractor’s Registration

New Jersey requires home improvement contractors to be registered with the state. The Division of Consumer Affairs oversees registration under the Contractors’ Business Registration Act and the Home Improvement and Home Elevation Contractor Licensing Act.⁷ Before signing a contract or issuing an ST-8, confirm the contractor holds a valid New Jersey Certificate of Authority number. That number is one of the required fields on the ST-8 itself.⁵

If the contractor lacks a Certificate of Authority, the ST-8 cannot be properly completed, and the sales tax exemption may not survive an audit. Verifying registration through the Division of Consumer Affairs takes a few minutes and protects both your exemption and your rights if a dispute later arises.

A Separate Local Program to Ask About

The sales tax exemption is a statewide rule. It’s distinct from New Jersey’s Five-Year Exemption and Abatement Law, which lets participating municipalities shield part of the added assessed value from local property taxes for up to five years after a qualifying improvement.⁸ Not every town offers it, deadlines vary locally, and missing a local deadline can forfeit the benefit entirely. If you’re planning a substantial project, ask your municipal tax assessor whether the town has adopted an ordinance and what the filing window looks like before work starts.

1
Legal Information Institute. N.J. Admin. Code 18:24-5.7 – Documentation and Application of the Capital Improvement Exemption
2
New Jersey Division of Taxation. Sales Tax and Home Improvements – Tax Topic Bulletin S&U-2
3
New Jersey Division of Taxation. NJ Division of Taxation – Sales and Use Tax
4
New Jersey Division of Taxation. Sales and Use Tax Forms and Certificates
5
State of New Jersey Division of Taxation. Sales Tax Form ST-8 Certificate of Exempt Capital Improvement
6
New Jersey Division of Taxation. Sales Tax Exemption Administration
7
New Jersey Division of Consumer Affairs. Regulated Business Section – Home Improvement Contractors
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Justia. New Jersey Code 40A:21-1 – Short Title