The Triple Net Lease, Explained End to End

“NNN” gets used loosely enough to cost people money. This is the precise version — what the structure is, the gradations that matter, how each side should read one, and the ownership job after closing — with the full FAQ library as backup.

The three nets, and who carries what

A triple net lease shifts the property’s three operating cost buckets to the tenant: property taxes, property insurance, and maintenance/CAM. The landlord receives base rent as net income. Against a gross lease (landlord pays everything from a fatter rent) or modified gross (split by negotiation), NNN is the structure that makes a building behave like a bond — which is exactly why 1031 buyers and retirees dominate the buyer pool.

The gradient: NN → NNN → absolute → ground

The label on the flyer is marketing; the maintenance article is the truth. NN (double net): tenant pays taxes and insurance; landlord keeps roof and structure — common at auto-parts and older dollar stores, priced 25–50 basis points wider for the capital exposure. NNN: tenant handles operating maintenance too; roof/structure allocation varies deal by deal. Absolute net: everything, without exception, is tenant obligation — the mailbox-money standard. Ground lease: tenant owns its building on your land; you hold dirt and collect rent, with reversion upside decades out. The lease-type map places each of these against gross and specialty forms.

A working glossary (the words that move money)

Base / primary term is the only period financing believes in — years before options start. Firm term is years before any kick-out or termination right; a long Walgreens headline can still be a short firm term. CAM on a single-tenant pad is the catch-all for site upkeep, capped or not. Dark means the store can close and rent continues — financing and resale still suffer. Escalations are the scheduled bumps (retail’s default cadence is 10% every five years). Estoppel is the tenant’s written confirmation of the deal (full explainer). Go-dark / kick-out rights let a tenant leave early on triggers; rare in this asset class, fatal to miss. NOI on absolute paper is effectively the rent. Options are the tenant’s renewal choices, never your certainty. Rent commencement is when money starts, which can lag lease commencement on a new pad. ROFR / ROFO give the tenant first crack at your sale and chill auctions. SNDA is the lender-tenant treaty. Words a listing package never defines are usually where the story lives.

Reading a lease like a buyer

Six clauses decide most of the value. The maintenance article (who owns the roof, the structure, the parking lot, the HVAC). Escalations (10%-per-five is the retail standard; flat legacy paper prices differently). Options and any termination rights (a Walgreens “75-year” lease is really its firm term). Assignment and subletting (how weak can your counterparty legally become?). Casualty and condemnation (who rebuilds, who can walk). And estoppel obligations (your resale depends on the tenant confirming the deal in writing). None of this is exotic — it’s an hour of careful reading that changes bids by six figures.

The maintenance article is the price

Value eventually collapses to one question: who owns each component at repair scale and at replacement scale. Read for roof membrane versus full replacement, structure, HVAC at end of life, parking mill-and-overlay, and the wet/electrical/fire systems. Strong paper assigns each item at both scales. Weak paper says “tenant shall maintain” and leaves the verbs for a later fight. Tenant repair does not automatically mean tenant replacement; on a twenty-year-old box that distinction is a five-figure line per system. Inspect as if you will inherit the building, because at expiration you do. Corporate national vendors and a franchisee in the last option year do not maintain the same way.

NN paper is where this math is first-order. A 7,000 SF membrane at $60–100K every 18–25 years, plus parking at a few dollars a foot on its own cycle, is how an advertised 6.4% becomes an economic 6.1%. A young membrane with a transferable warranty almost erases the extra capital risk; an original roof from the early 2000s is the entire extra risk. Some forms give the tenant repairs and the landlord replacement — worth exactly one roof.

Insurance, legal, and the books

The tenant should carry replacement-cost property (landlord as loss payee), CGL with the owner as additional insured, and its own business interruption. Keep a thin contingent policy anyway: lapse, dispute, and suits that name the fee owner are the gaps. Collect certificates, calendar renewals, and ask for the actual endorsements — a checkbox on a certificate is not the endorsement. Coastal wind and hail-belt roofs now sit inside tenant occupancy cost, which makes them your renewal-probability input even though the invoice is theirs.

Disputes, when they happen, cluster: maintenance boundaries, casualty proceeds and rebuild standards, assignment to a weaker entity, and defaults run off the lease’s literal notice-and-cure path. Courts forgive landlords almost nothing procedurally. Drafting that names components and replacement thresholds is cheaper than the later letter.

Individual owners mostly live on cash-basis Schedule E. If the tenant pays tax and insurance straight to the county and carrier, those amounts never hit your return; if they reimburse you, book both sides. GAAP entities straight-line rent, so contractual bumps become a receivable. Keep the file a future buyer or lender will ask for: lease set, estoppels, certificates, tax receipts.

Tax: the two large items and the shadows

On absolute paper the operating stack is the tenant’s, so your deductions concentrate. Depreciation on the improvement allocation (commercial: 39 years; cost segregation can pull site-work forward — confirm current bonus percentages with your CPA) and interest on the loan do the heavy work. Land never depreciates, which is why the closing allocation is not a clerical line. Professional fees, entity costs, and inspection travel are the residue. Reserves are not deductible until spent, and capital replacements depreciate rather than expense.

QBI’s 20% deduction reaches some NNN facts and misses others — Rev. Proc. 2019-38’s hour tests were written for active rentals. Get a written position. Passive-loss rules can bank paper losses for high earners until a sale. Every depreciation dollar taken now waits at 25% later, unless a 1031 exchange keeps deferring it or a step-up at death clears the ledger.

The ownership calendar after closing

Monthly: confirm the rent hit. Quarterly: ratings actions, closure lists, franchisee trades. Annually: certificate plus endorsements, county payment if the tenant remits direct (delinquency mail is yours even when the check is not), the tax return, and a drive-by or commissioned photos. Per the lease: option windows and bump dates in the lease expiry tool. NN adds inspections and reserves. Distress adds counsel and the lease’s default script. Vacancy is a second career — the scenario purchase-day basis was supposed to price.

Most single-asset owners self-manage in a handful of hours a year. Hire help for the next acquisition, where criteria and underwriting actually move numbers.

Where NNN goes wrong — and the honest trade

Predictable places: buying “NNN” that’s contractually NN with a 20-year-old roof; above-market rent from a sale-leaseback that resets down at renewal; strong-credit tenants in re-lease-proof buildings; and CAM caps or landlord-liability edges hiding in reimbursement language. Every one is visible before closing to whoever actually reads — the argument, as ever, for representation that reads for a living.

The genuine advantages are real passivity on absolute paper, credit-backed income, 10–20 year math you can retire on, lenders who quote the product daily, and 1031 compatibility. The drawbacks are equally real and all priceable: one tenant is 100% vacancy, single-purpose boxes re-tenant at a haircut, flat stretches erode against inflation, long duration reprices with yields, and options belong to the tenant. NNN is not risk-free income. It is risk you can read, sitting in a lease you can hold.