Commercial Lease True Cost Calculator

Stop guessing your monthly rent. Calculate NNN fees, check industry benchmarks, and uncover red flags instantly.

sq ft
Monthly Base Rent $0.00
Monthly NNN Fees Taxes + Insurance + CAM
+$0.00
Estimated Total Check Written $0.00
Industry Health Score 0%

Enter your projected sales to run a standard rent-to-revenue health check.

The Logic: How the Math Works

Commercial real estate math is intentionally complex. Here is the breakdown of your calculation.

1

The Base Rent Equation

We take your Rentable Square Footage (RSF) and multiply it by the annual rate, then divide by 12. Most people stop here, but this is merely the "entrance fee" for the building.

2

Triple Net (NNN) Pass-Throughs

In a Triple Net lease, the landlord passes their operating costs directly to you. This includes Property Taxes, Building Insurance, and CAM (Common Area Maintenance). These are variable costs that can spike unexpectedly based on building needs or tax assessments.

3

Load Factor & Efficiency

You pay for "Rentable" space, but you only live in "Usable" space. The Load Factor (usually 10-20%) is essentially a "hallway tax" that pays for shared lobbies and elevators. If your load factor is too high, you are paying rent on square footage you can't actually use for business.

Lease Decoder Glossary

Plain-English definitions for the terms that matter most to your bottom line.

Good Guy Guarantee (GGG)
Common in NYC, this limited guarantee releases the individual from personal liability once the tenant vacates the space, returns keys, and leaves it in "broom-clean" condition, provided rent is paid through the surrender date.
CAM (Common Area Maintenance)
Expenses for operating shared spaces like lobbies, parking lots, and landscaping. At year-end, landlords "reconcile" estimated CAM fees against actual costs, which can result in an unexpected bill if the building was over-maintained.
TI (Tenant Improvement) Allowance
Funding provided by the landlord for build-outs. Be wary of "Disbursement timing"—many landlords only reimburse *after* completion, which creates a massive upfront cash flow burden for small businesses.
Holdover Clause
A penalty for staying past your lease expiration. In many commercial markets, this can instantly jump your rent to 150% or even 300% of your previous rate.
Modified Gross Lease
A hybrid lease structure where the landlord and tenant share specific operating expenses. This is highly negotiable and requires careful review of who pays for janitorial, utilities, and minor repairs.
Percentage Rent (Natural Break)
In retail, you may pay a base rent plus a % of gross sales once you hit a "natural break" point—the level where the percentage of your sales equals your base rent.

Standard Rent-to-Revenue Health Checks

2-7%
Office
8-12%
Retail
6-10%
Restaurant
5-10%
Medical

Frequently Asked Questions About Commercial Leases

What is a Triple Net (NNN) lease?

In a Triple Net lease, the tenant pays a lower base rent but takes on the responsibility for their share of the building's property taxes, building insurance, and common area maintenance (CAM). Your base rent is only the starting point—your true monthly cost will be significantly higher once these three "nets" are added.

What are Common Area Maintenance (CAM) fees?

CAM fees cover the operational costs of maintaining shared spaces in a commercial property. This typically includes landscaping, snow removal, parking lot maintenance, exterior lighting, and shared janitorial services. These fees are divided among tenants based on the square footage they occupy.

How does the "Load Factor" affect my commercial rent?

In commercial real estate, you do not just pay for your private office space (Usable Square Footage). You also pay for a percentage of the shared spaces, like lobbies, hallways, and restrooms. The Load Factor is the multiplier used to calculate your Rentable Square Footage, which is the higher number your landlord actually uses to determine your monthly rent.

What is a Tenant Improvement (TI) Allowance?

A TI allowance is a sum of money a landlord provides to help a tenant customize or build out their commercial space, usually expressed as a dollar amount per square foot. It is important to calculate this carefully; if your construction costs exceed the allowance, you are responsible for covering the difference out of pocket.

Why is my actual commercial rent higher than the quoted price?

Landlords often quote the "base rent" annually per square foot because it looks appealing. To find your true monthly cost, add your estimated CAM fees, taxes, and insurance, then apply your building's load factor. Using a commercial lease calculator ensures you see the final monthly check you will write, not just the promotional base rate.