NNN vs. Gross Lease vs. Modified Gross: Which Structure Protects Landlords Most?

Introduction

This guide breaks down the three most common commercial lease structures, compares them head-to-head, and explains which one tends to favor landlords, which favors tenants, and when each makes sense.

The Core Concept: Who pays operating expenses?

All commercial lease structures can be understood through one lens: who is responsible for the property's operating expenses? These typically fall into three categories:

•       Property taxes

•       Building insurance

•       Maintenance and repairs (including common area maintenance, or CAM)

Depending on the lease type, these costs fall entirely on the landlord, entirely on the tenant, or are split in some agreed-upon way.

Triple Net Lease (NNN) Structure

How it works

In a triple net lease, the tenant pays base rent plus all three operating expenses: property taxes, insurance, and maintenance. The landlord receives a predictable net check each month with minimal obligation.

Who Benefits

Landlords, significantly. The NNN structure is prized by investors because it eliminates most expense variability. If property taxes rise, the tenant absorbs the increase. Landlords essentially own a passive income stream.

Best for

•       Single-tenant retail (think fast food, pharmacies, dollar stores)

•       Long-term leases with creditworthy national tenants

•       Investors seeking low-management, bond-like returns

Watch out for

NNN leases with smaller or less creditworthy tenants carry more risk than they appear if the tenant struggles, so does your income. Also, 'NNN' isn't standardized; always read the lease to confirm what net means in each deal.

Gross Lease (full service lease) Structure

How it works

In a gross lease, the tenant pays a single all-inclusive rent figure. The landlord collects that rent and pays all operating expenses out of it. It's simpler for tenants  they know exactly what they're paying each month.

Who Benefits

Tenants. The gross lease provides cost certainty and removes the burden of managing operating expense reconciliations. Landlords take on the risk that expenses will rise if operating costs increase faster than rent, margins shrink.

Best for

•       Office buildings (especially multi-tenant)

•       Tenants who want budgeting simplicity

•       Shorter-term leases where expense tracking is burdensome

Watch out for

Landlords in gross leases should include expense stop clauses  a threshold above which the tenant begins sharing in cost increases. Without this protection, unexpected expense spikes can devastate returns.

Modified Gross Lease Structure

How it works

The modified gross (or 'modified net') is a negotiated hybrid. Tenant and landlord split operating expenses in a customized way typically the landlord covers some base expenses, while the tenant handles others or pays their proportionate share of increases above a base year.

Who Benefits

Neither party exclusively  that's the point. Modified gross leases are designed for flexibility, making them popular in multi-tenant office and mixed-use properties where tenant needs vary.

Best for

•       Multi-tenant office and creative/flex space

•       Deals where standard NNN or gross structures don't fit

•       Markets where lease terms are heavily negotiated

Watch out for

Complexity. Modified gross leases require careful drafting. Both parties must be precise about which expenses are included, how CAM reconciliations work, and what the base year figures are.

Which Structure Suits Landlords Best?

The answer depends on your goals and asset type:

•       If you want passive, low-management income: pursue NNN deals with national credit tenants. You'll accept a lower cap rate in exchange for certainty.

•       If you own a multi-tenant office building: modified gross or gross leases are market standard. Focus on strong expense stops and base year definitions to protect your margins.

•       If you're in a tenant's market (high vacancy, competitive rents): you may not have the leverage to demand full NNN terms. Flexibility on lease structure can be what closes a deal.

Final Thoughts

There's no universally 'best' lease structure — there's only the right structure for your asset, market, and tenant mix. What matters most is that you understand the economics fully before you sign.

A seasoned commercial real estate attorney and a capable broker can be invaluable here. The lease structure you negotiate today will govern your returns for the lease term.