New Jersey mechanics lien law: deadlines, the NUB, and what trips up contractors

If you ran a job in California or Texas and assumed New Jersey works the same way, you're about to lose a lien.

New Jersey's Construction Lien Law adds a step that most other states don't have: on residential projects, you have to file a Notice of Unpaid Balance and Right to File Lien (NUB), demand arbitration through the American Arbitration Association, and get an arbitrator's decision before you can record an actual lien. The whole detour lives in N.J.S.A. 2A:44A-1 through -38, and the deadlines are short, strict, and unforgiving.

This post walks through the statute, the residential NUB process, the commercial 90-day track, and the four mistakes that kill New Jersey liens before they ever get filed.

The legal anchor

New Jersey's Construction Lien Law sits at N.J.S.A. 2A:44A-1 to -38. It took effect on April 22, 1994, replacing the older Mechanics' Lien Law, and it's been amended several times since (most importantly in 2010, which tightened the residential arbitration framework).

The statute applies to any contractor, subcontractor, or supplier who furnishes work, services, materials, or equipment under a written contract. The "written contract" piece is load-bearing. New Jersey does not give lien rights for handshake deals or back-of-a-business-card scribbles. If the contract was verbal, you have no lien.

The other thing to internalize before reading further: New Jersey runs two parallel tracks depending on whether the property is residential or non-residential. The deadlines are different. The pre-filing requirements are different. Confusing the two is the most common reason a New Jersey lien fails on procedural grounds.

Commercial projects: the 90-day track

For non-residential projects (offices, warehouses, retail, industrial, public infrastructure that isn't a public-funds job), the timeline is straightforward by New Jersey standards.

You have 90 days from the last day you provided labor, materials, or services to file the lien claim with the county clerk in the county where the property sits. The form is prescribed at N.J.S.A. 2A:44A-8 — it has to be signed, acknowledged, and verified by oath of the claimant. No notary, no statutory form, no lien.

Within 10 days of filing, you have to serve a copy of the signed lien claim on the property owner and on every contractor above you in the chain. Personal service or registered/certified mail. Email doesn't count. Texts don't count. If you blow the 10-day service window, the lien is forfeit even though it was filed on time.

Then you have one year from the last day of work to commence a foreclosure suit in Superior Court under N.J.S.A. 2A:44A-14. Miss that, and the lien evaporates — recorded but unenforceable, which is the worst of both worlds.

That's the commercial track in three numbers: 90 / 10 / 365.

Residential projects: the NUB and arbitration detour

This is where New Jersey is genuinely strange.

If the property is residential, which the statute defines roughly as one- and two-family homes occupied or intended to be occupied by the owner, you cannot file a lien directly. You first have to file a Notice of Unpaid Balance and Right to File Lien, called the NUB in everyday speech, with the county clerk. The form sits at N.J.S.A. 2A:44A-20, and it has to include the same information as a lien claim: who you are, what you did, who hired you, the unpaid balance, and where the property is.

The NUB itself isn't a lien. It's a placeholder that signals you're going to claim one. Once filed, you have to serve it on the owner and the prime contractor, and you have to file a Demand for Arbitration with the American Arbitration Association before the 60th day from your last day of work.

Practically: don't try to thread this on day 59. The American Arbitration Association needs the demand received and processed before the 60-day clock runs out. Most New Jersey construction lawyers will tell you to file the NUB by day 40 and the AAA demand by day 50, just to keep daylight between you and the deadline.

The arbitrator then has 30 days to decide two things: whether you have valid lien rights and how much you can lien for. The decision narrows or confirms the lien fund, which is the pool of money the lien can attach to under N.J.S.A. 2A:44A-9, based on what's actually owed up the chain.

Once the arbitrator rules in your favor, you have 10 days from the award to record the actual lien claim with the county clerk. And the entire residential process (NUB, arbitration, lien filing) has to wrap inside 120 days of your last day on the job. After that, even a winning arbitration award won't save you.

That's the residential track: 60 / 30 / 10 / 120. Four numbers, one mandatory detour, and a process most out-of-state contractors discover the hard way.

The lien fund and why your number can shrink

A New Jersey lien doesn't automatically attach for the full amount on your invoice. It attaches up to the lien fund — the amount the owner still owes the prime contractor (or that the prime owes the sub above you) at the moment the lien is filed.

If the owner already paid the prime in full, the lien fund is zero, and your lien is functionally worthless even though it's recorded. This is why subs in New Jersey care intensely about whether the owner has paid the GC, and why a working lien waiver software workflow matters more here than in single-tier states. The signed waivers in your dashboard are the evidence that controls the lien fund calculation.

The priority rules are also worth knowing. A lien filed under the Construction Lien Law has priority over a later mortgage or conveyance — but only if a NUB or lien claim was filed before the mortgage was recorded. Banks know this, which is why you see N.J.S.A. 2A:44A-6 referenced in title commitments on every active New Jersey job.

The four mistakes that kill New Jersey liens

After a few hundred filings worth of pattern-matching, the procedural failures cluster into four buckets:

• Treating residential like commercial. Skipping the NUB and going straight to a lien on a single-family home gets the claim discharged on a motion. Always confirm the property type before you start counting days.
• Missing the 10-day service window. The lien is filed on day 89, and then the certified mail goes out on day 100. The court treats this as fatal. Calendar the service date the same hour you calendar the filing date.
• Working without a written contract. N.J.S.A. 2A:44A-3 is unambiguous. A verbal change order on top of a written prime contract usually survives, but a wholly verbal scope does not. Get the scope in writing before the first day on site.
• Letting the one-year enforcement clock run. Filing a lien is the start, not the finish. If you don't sue to foreclose within one year of the last day of work, the lien dies on the calendar. This catches more contractors than any other rule because the one-year deadline lives outside the day-to-day filing rhythm.

Lien waivers in the New Jersey workflow

Lien waivers and lien filings sit at opposite ends of the same workflow. You collect signed waivers as payments go out so you have evidence the lien fund has been paid down. You file a lien when payments stop and the waivers stop coming back.

New Jersey doesn't prescribe a statutory waiver form the way California does for its four Civil Code waivers. You can use any form that clearly identifies the claimant, the through-date, and the amount waived. The four-type framework still applies, though: conditional progress, unconditional progress, conditional final, unconditional final. Getting the matching type signed at every payment is what keeps the lien fund math clean if a dispute starts.

For the day-to-day mechanics of getting subs to actually sign, conditional vs unconditional lien waivers covers the four-type framework that applies in every state. The New Jersey state page has the form generator for the four types pre-filled with NJ-appropriate defaults.

If you're working multi-state, the deadline tables in our Florida lien waiver, Arizona lien waiver and release forms, Louisiana mechanics lien, and Idaho lien filing guide posts use the same calendar-first format, so you can spot the differences at a glance.

How LienDone handles New Jersey

When you pick New Jersey in the form selector, LienDone fills in a waiver that satisfies the standard four-type framework with NJ-specific defaults: through-date, claimant identification, owner, job address, and unpaid balance pre-populated from your project and pay app data.

For the lien-side workflow, the platform tracks the dates that matter: last-furnishing date per contract, the 60-day NUB clock for residential jobs, the 90-day filing clock for commercial, and the 10-day service window. Notifications fire at day 30, day 50, and day 80 so the deadlines don't slip by accident.

The signed PDFs and the deadline log live in the same dashboard. If a dispute does land in arbitration, you have one place to pull the entire payment-and-waiver history from instead of digging through three years of email threads.

The takeaway for New Jersey GCs

Two tracks. One statute. The residential NUB-and-arbitration detour is the part that catches out-of-state contractors and the part that turns a 90-day filing into a 120-day procedural maze.

The shortest path through the law:

1. Decide residential or non-residential before day one of the job.
2. Get the contract in writing.
3. Send conditional waivers with every progress payment, unconditional only after funds clear.
4. If payment stops, file the NUB by day 40 (residential) or the lien claim by day 80 (commercial). Don't sail close to the deadlines.
5. Sue to enforce inside the one-year window, or watch the lien dissolve.

Most New Jersey lien losses aren't substantive. They're procedural. The dollars were owed, the work was done, the contract was real — the calendar just won.

FAQ

What is the deadline to file a mechanics lien in New Jersey?

90 days from the last day of work for non-residential projects. For residential projects, file the NUB and demand AAA arbitration within 60 days, then file the actual lien within 10 days of the arbitrator's award and within 120 days total.

Do I need to file a Notice of Unpaid Balance before a lien in New Jersey?

Only on residential projects. Commercial projects skip the NUB and go straight to a lien claim under N.J.S.A. 2A:44A-8.

How long do I have to enforce a New Jersey mechanics lien?

One year from the last day you provided work or materials, under N.J.S.A. 2A:44A-14. Miss the deadline and the lien is unenforceable.

Does a New Jersey lien require a written contract?

Yes. N.J.S.A. 2A:44A-3 requires the work to have been performed under a written contract.

Who has to be served after a lien is filed in New Jersey?

Within 10 days of filing, the claimant must serve a copy on the owner and on the contractor above them in the chain by personal service or registered/certified mail.

Can I file a lien on a public project in New Jersey?

No. Public projects fall under the Municipal Mechanics Lien Law and the bond claim process, not the Construction Lien Law.