Know Your True Monthly Occupancy Cost Before You Sign the Lease
Estimate monthly occupancy costs for office, retail, or industrial space. Calculates Base Rent, NNN / CAM charges, and projects your full lease cost with annual escalations.
| Year | Base Rate (PSF) | NNN (PSF) | Monthly Base | Monthly NNN | Monthly Total | Annual Cost |
|---|---|---|---|---|---|---|
| Calculate to see schedule | ||||||
Calculate to see schedule
How to Use the Commercial Lease Calculator
Getting a complete occupancy cost picture takes about two minutes. Enter your space details, rent structure, and lease terms — the calculator instantly shows your monthly cost, total contract value, and a full year-by-year escalation schedule.
Enter Space Details
Input the rentable square footage and select your space type — office, retail, industrial, or medical. The rentable area includes your usable space plus a share of common areas (typically 10–20% more than what you actually occupy). If you’re comparing multiple spaces, run each one separately and compare the monthly totals.
Add Rent & Charges
Enter the annual base rent per square foot (from your Letter of Intent or broker’s quote), the NNN/CAM charge per square foot, any tenant improvement allowance the landlord has offered, and any free rent months included in the deal. These concession fields directly reduce your net effective rent — the true average monthly cost after landlord contributions are factored in.
Set Term & Escalation
Choose your lease term (1–15 years) and annual escalation rate. Most U.S. leases escalate 2–4% per year. Use the escalation slider to instantly compare how different rates affect your total contract value over the full term. Enable the NNN escalation toggle if your lease specifies that CAM charges also increase annually — this produces a more conservative (and often more realistic) projection.
Review Results & Download the Report
The results card shows your Year 1 monthly cost, full cost breakdown, 6 key financial figures, and two charts — a cost composition doughnut and a stacked annual escalation bar chart. Open the accordion to see the complete year-by-year lease schedule with each year’s base rate, NNN, monthly total, and annual cost. Download the two-page PDF to share with your broker, CFO, or attorney before signing.
What This Calculator Shows You
Most commercial rent calculators multiply square footage by rate and stop there. This tool gives you the full occupancy cost picture — including NNN charges, annual escalations, landlord concessions, net effective rent, and a professional two-page PDF report for lease negotiations.
Total Monthly Occupancy Cost — Hero Figure
The results panel leads with your all-in monthly cost for Year 1: base rent plus NNN/CAM charges. The sub-label shows each component separately so you can immediately see how much of your monthly payment goes to base rent versus operating expense pass-throughs — which are often 20–35% of total occupancy cost in NNN leases.
Net Effective Rent — True Cost After Concessions
Net effective rent is the real average monthly cost of the lease after landlord concessions (TI allowance and free rent months) are subtracted from the total contract value and spread across the full term. This is the most accurate metric for comparing two lease offers with different concession packages — a high face rent with generous TI may be cheaper than a low face rent with no concessions.
6-Card Key Figures Summary
At-a-glance summary cards display total contract value, net effective monthly rent, effective PSF per year, annual base rent, annual NNN/CAM, and total landlord concessions — all updated in real time. These six figures give you everything you need to present the deal economics to a CFO, lender, or business partner in a single view.
Stacked Annual Escalation Bar Chart
A stacked bar chart shows base rent (blue) and NNN/CAM (red) for each year of the lease term. As rent escalates annually, the bars grow taller — making the compounding cost of escalation immediately visible. This chart is especially useful for long-term leases where the difference between Year 1 and Year 7 or Year 10 rent can be substantial.
Cost Composition Doughnut Chart
A doughnut chart shows the proportional split between base rent and NNN/CAM in Year 1. This is a quick visual check on whether your NNN charges are in a normal range (typically 20–35% of total occupancy cost) or unusually high — which could indicate that the quoted base rent is artificially low and the true cost is being shifted to operating expenses.
Year-by-Year Schedule + 2-Page PDF
The accordion schedule table shows every year of the lease: base rate per square foot, NNN per square foot, monthly base, monthly NNN, monthly total, and annual cost — with Year 1 highlighted in blue. The two-page PDF includes the full summary, breakdown table, charts, concessions analysis, and a year-by-year schedule with totals — formatted for landlord negotiations and internal finance review.
Commercial Real Estate — By the Numbers
How Different Tenants Use This Calculator
Whether you’re a growing startup signing your first office lease, a retailer comparing locations, or a CFO reviewing occupancy budgets, the numbers you need to focus on differ by situation. Here’s how three common tenant types approach the analysis.
The Business Owner / Startup
First commercial lease — understanding total costYou’ve been quoted a base rent rate by a broker and want to understand what you’ll actually pay each month — including NNN charges, how much costs will increase over time, and what the landlord’s TI offer is really worth before you negotiate.
- Enter the base rate and NNN from the broker’s quote — see the true all-in monthly cost, not just the headline number
- Add the landlord’s TI allowance to the calculator — it directly reduces your net effective rent and shows how much of the build-out cost they’re absorbing
- Run the escalation at 3% and 4% to see the total contract value difference over a 5-year term — this is your negotiating data point
- Download the PDF and share with your accountant or attorney before signing to confirm the numbers match the lease document
The Retailer Comparing Locations
Evaluating multiple lease offers side by sideYou have two or three retail spaces under consideration with different sizes, rates, NNN charges, and concession packages. You need a fast, accurate way to compare the true economics of each deal — not just the monthly payment, but total cost and net effective rent.
- Run each location separately and note the net effective rent — this is the only truly comparable figure when concession packages differ
- A higher base rent with more free months and stronger TI often beats a lower base with no concessions — this calculator makes that visible instantly
- Compare total contract values: a 5-year lease at $28/sf with 3% escalation may cost more than a 5-year lease at $30/sf with 2% escalation
- Use the year-by-year table to confirm you can absorb the rent in later years — the Year 5 payment is what matters for long-term sustainability
The CFO / Finance Team
Occupancy budget modeling & lease reviewYou’re modeling commercial occupancy costs for a budget cycle, preparing for a lease renewal negotiation, or reviewing a proposed lease against your real estate spend targets. You need accurate, exportable numbers with all components clearly itemized.
- Enable NNN escalation for a conservative model — CAM charges typically rise 3–5% annually in practice even when not specified in the lease
- Use net effective rent as your budget line item, not face rent — it is the economically accurate figure for financial statements and lease comparisons
- The year-by-year PDF table maps directly to a multi-year occupancy budget — each row is one fiscal year of committed lease cost
- Run the full term at 0% escalation vs. 3% escalation to show leadership the financial exposure range before entering lease negotiations
7 Things to Know Before Signing a Commercial Lease
Commercial leases are long-term commitments with terms that favor landlords by default. These seven factors are the most commonly misunderstood — and the most financially significant — for business tenants.
NNN Charges Are Estimates — Reconciled Annually
Landlords estimate NNN charges at the start of each year based on projected operating costs. At year-end, they reconcile actual expenses against estimates. If actual costs exceeded the estimate, you owe the difference — often a significant “true-up” payment. Always request the prior two years of actual CAM reconciliation statements before signing a NNN lease to verify that estimates are realistic and not systematically underquoted to make the space look cheaper.
Always Negotiate a CAM Cap
Many commercial leases allow CAM charges to increase without limit year over year. Negotiating a CAM cap — typically 5–7% per year — protects you from unexpected spikes in operating expenses being passed through to you. Some leases also allow “controllable” and “uncontrollable” CAM expenses to be capped separately, with taxes and insurance excluded from the cap. A tenant-side CRE attorney will negotiate this clause; never accept unlimited CAM increases without pushback.
Rentable vs. Usable Square Footage Changes Your Rate
Always confirm whether a quoted rate applies to usable or rentable square footage before comparing two spaces. A 2,000 usable sf space at $30/sf rentable (with a 15% load factor) is actually 2,300 sf of rent at a net-usable cost of $34.50/sf — significantly more expensive than it appears. Request the floor plan measurement method and load factor in writing from the landlord before calculating costs.
Tenant Improvement Allowance Is Not Free Money — Plan It Carefully
TI allowances are typically paid by the landlord after construction is complete, not upfront. This means you need to fund the build-out initially and be reimbursed — which requires working capital or a construction line of credit. Additionally, TI that exceeds the allowance is your cost. Work with a contractor to develop a realistic build-out budget before accepting a TI amount and signing a lease based on it. Underfunded TI is one of the most common budget surprises for new commercial tenants.
Understand Your Personal Guarantee Exposure
Most commercial landlords require a personal guarantee from the business principals, making you personally liable for all lease obligations if the business fails. The length of the personal guarantee is negotiable — push for a “burn-down” guarantee that decreases year by year, or cap your personal exposure at 12–18 months of rent rather than the full lease term. For multi-year leases, the uncapped personal guarantee can represent hundreds of thousands of dollars of personal liability.
Model the Last Year of the Lease, Not Just Year 1
Tenants often approve a lease based on the Year 1 monthly payment without fully appreciating what rent will be in Year 5 or Year 7 after annual escalations compound. Use the year-by-year table in this calculator to see your exact monthly payment in every year of the lease term. The last year’s rent is the figure that determines whether a lease renewal is affordable — and it’s the number you should budget to when planning a long-term location.
Hire a Tenant-Side CRE Broker — Their Commission Is Paid by the Landlord
In commercial real estate, both the listing broker (representing the landlord) and the tenant’s broker are paid by the landlord from the lease commission — meaning tenant representation is effectively free for the business. A good tenant-side broker will negotiate rent reductions, TI allowances, free rent months, CAM caps, renewal options, and favorable exit clauses that inexperienced tenants routinely leave on the table. Never negotiate a commercial lease directly against an experienced listing broker without representation on your side.
Commercial Lease — FAQ
Real questions from business owners and tenants navigating commercial leases — answered plainly.
Important disclaimer: All calculations provided by this tool are for educational and estimation purposes only and do not constitute financial, legal, or real estate advice. Results are based on the inputs you provide and standard NNN lease calculation methods. Actual lease costs vary significantly by market, landlord, building class, lease structure, and individual deal negotiation. NNN/CAM charges are annual estimates and are typically reconciled against actual operating expenses at year-end — actual charges may differ from estimates. This tool does not account for gross lease structures, modified gross leases, percentage rent clauses, operating expense caps, exclusions, or other lease-specific provisions. Always review the complete lease document with a licensed commercial real estate attorney and consult a qualified CRE broker before signing any commercial lease agreement. HomeExpertly is not a licensed real estate broker, attorney, or financial advisor.