Commercial Real Estate Rent Calculator
Enter your square footage, rate, and lease type to see your true monthly and annual commercial rent — base rent plus NNN or CAM, not just the headline number.
Why commercial rent is harder to calculate than it looks
A residential rent quote is simple: the number on the listing is the number you pay. Commercial rent doesn't work that way. A quote like "$28/SF/yr NNN" packs three separate pieces of information into one line — a base rate, a billing convention, and an implied set of extra charges you won't see until the lease itself spells them out. This calculator exists because the gap between a headline rate and the actual monthly invoice catches a lot of first-time commercial tenants off guard.
Enter your square footage, your quoted rate, and your lease type, and this tool builds out the full picture: base rent, NNN or CAM pass-throughs where they apply, your true all-in rate per square foot, and how the numbers shift across a multi-year lease term with a standard annual escalation applied.
The commercial rent formula, by lease type
Every commercial lease starts from the same base calculation, then layers on different expenses depending on the structure:
Annual Base Rent = Rate per SF/Year × Square Footage
A 2,500 SF space quoted at $28/SF/year costs $70,000 in annual base rent before any additional charges, or $5,833.33 per month.
Triple Net (NNN)
Total = Base Rent + (NNN Rate × SF)
The tenant pays base rent plus a separate per-square-foot charge covering property taxes, building insurance, and CAM. Most common in retail and industrial leases.
Modified Gross (MG)
Year 1 = Base Rent only
The landlord covers a base year of expenses. From year two onward, the tenant pays their share of any increase in expenses above that base year — a smaller, growing pass-through rather than a fixed NNN rate from day one.
Full-Service Gross (FSG)
Total = Base Rent (everything included)
Taxes, insurance, CAM, and often utilities are baked directly into the quoted rate. The number you see is the number you pay, with no separate line items. Common for Class A office space in major business districts.
This calculator applies the NNN formula when you select that lease type, skips the NNN field entirely for Full-Service Gross, and treats Modified Gross as base rent only for year one — the most common simplification used in early-stage lease comparisons, since the actual MG pass-through depends on expense increases that haven't happened yet.
Usable vs. rentable square footage — the detail tenants miss
Before you even apply a rate, it's worth checking which square footage number you're actually being quoted against. Usable square footage (USF) is the floor space your business physically occupies. Rentable square footage (RSF) adds your proportional share of the building's common areas — lobbies, hallways, shared restrooms, elevator banks — using what's called a common area factor.
Most commercial landlords bill on RSF, not USF. A building with 100,000 total square feet and 20,000 square feet of common area has a common area factor of 20%. A tenant occupying 10,000 USF in that building is actually billed at 12,000 RSF — a difference that, at $28/SF/year, adds an extra $56,000 annually the tenant wouldn't expect if they were calculating off USF alone. Always confirm which figure your quote is using before you run it through this calculator.
Typical commercial rent rates by property type (2026)
Rates vary enormously by city and building class, but these national benchmarks give a useful starting point for sanity-checking a quote:
| Property Type | Typical Rate ($/SF/Year) | Common Lease Type |
|---|---|---|
| Office (Class A, major CBD) | $40 – $80+ | Full-Service Gross |
| Office (general) | $20 – $50 | Modified Gross / FSG |
| Retail | $18 – $40 | Triple Net (NNN) |
| Medical Office | $24 – $38 | NNN or Modified Gross |
| Industrial / Warehouse | $8 – $15 | Triple Net (NNN) |
NNN charges themselves typically add $3 to $16 per square foot annually on top of base rent, with newer Class A buildings running toward the higher end and older flex or industrial space toward the lower end. CAM alone — separate from taxes and insurance — often runs $4 to $12 per square foot depending on the property's age and amenity load.
Worked examples
2,500 SF retail space, NNN
Base rate: $28/SF. NNN rate: $9/SF. Annual base = $70,000. Annual NNN = $22,500. Total annual = $92,500, or $7,708.33/month — an all-in rate of $37/SF/year, 32% above the headline $28 figure.
5,000 SF office, Full-Service Gross
Base rate: $35/SF. No separate NNN line. Annual cost = $175,000, or $14,583.33/month, with no additional charges to budget for beyond the quoted rate.
10,000 SF industrial, NNN, 5-year term
Base rate: $11/SF. NNN rate: $4/SF. Year 1 total = $150,000. With a 3% annual base rent escalation over a 5-year term, the cumulative cost reaches roughly $809,000, averaging about $13,483/month across the full term.
3,000 SF medical office, Modified Gross
Base rate: $30/SF. Year 1 annual = $90,000, or $7,500/month, treated as base-rent-only since the expense base year hasn't generated a pass-through yet. Expect a modest increase in year two as actual expenses are reconciled against the base year stop.
Common mistakes when budgeting for commercial rent
A $32 base + $11 NNN space is $43/SF all-in, not $32. Plenty of new tenants budget for the base alone and get blindsided when the first NNN invoice arrives.
If your quote is based on RSF and you calculate against USF, you'll underestimate your real cost — sometimes by 15-20% in buildings with a high common area factor.
A flat-looking quote can still carry a 2-4% annual bump, or a CPI-linked increase. Over a 5 or 10-year term, that compounds into a meaningfully higher average monthly cost than the year-one figure suggests.
Landlords sometimes offer a higher tenant improvement allowance in exchange for a higher base rate. That allowance is effectively amortized into your rent, not a giveaway — compare total occupancy cost, not just the headline TI number.
More finance calculators on CalcMora
Commercial rent is just one recurring cost in a much larger budget picture, and a few other tools on CalcMora help round that out. If your business also finances vehicles for delivery or staff, the monthly car payment calculator breaks down financed vehicle costs the same way this tool breaks down rent — rate, term, and total cost over time. For leased company vehicles specifically, the money factor calculator converts a lease's money factor into an effective interest rate, similar to how this tool converts a quoted rent rate into a true all-in cost per square foot. If you're weighing leasing commercial space against buying a property outright, the mortgage calculator lets you compare a purchase scenario side by side with the lease numbers above. And if recent payroll rules affect how you're budgeting staff costs alongside rent, the no tax on overtime calculator helps estimate the net effect on take-home pay for hourly staff working extra hours in the space you're leasing.
Commercial real estate rent calculator — FAQ
How do I calculate commercial rent per square foot?
Multiply your quoted rate per square foot per year by your total square footage to get annual base rent, then divide by 12 for the monthly base rent. For example, a 2,500 square foot space at $28 per square foot per year costs $70,000 annually, or $5,833.33 per month, before any NNN, CAM, or other pass-through expenses are added on top.
What is the difference between NNN, modified gross, and full-service gross leases?
In a Triple Net (NNN) lease, the tenant pays base rent plus their share of property taxes, building insurance, and common area maintenance separately, on top of the quoted rate. In a Modified Gross lease, the landlord covers some operating expenses (often a base year of taxes and insurance) while the tenant covers increases above that base year. In a Full-Service Gross (FSG) lease, the quoted rate already includes all operating expenses, so the rent you see is the rent you pay, full stop.
What is included in CAM (Common Area Maintenance) charges?
CAM charges cover the shared costs of running a multi-tenant property: parking lot maintenance, landscaping, snow removal, common-area lighting, security, property management fees, and sometimes a portion of capital repairs like roof or HVAC replacement, amortized over several years. Typical CAM charges run $4 to $12 per square foot annually, though this varies significantly by property type and region.
What is the difference between usable square footage and rentable square footage?
Usable square footage (USF) is the actual floor area your business occupies. Rentable square footage (RSF) adds your proportional share of shared common areas — hallways, lobbies, restrooms, elevator banks — calculated using the building's common area factor. Most commercial landlords quote and bill rent based on RSF, not USF, so a 10,000 square foot office in a building with a 20% common area factor might actually be billed at 12,000 RSF.
What is a typical commercial rent rate by property type?
As a general 2026 benchmark in the U.S., office space typically runs $20 to $50 per square foot annually depending on class and market, retail runs $18 to $40 per square foot, industrial and warehouse space runs $8 to $15 per square foot, and medical office space runs $24 to $38 per square foot. Major metro cores like New York or San Francisco can push Class A office rates well above $80 per square foot, while smaller markets often sit under $20.
How much of my business revenue should go toward commercial rent?
A commonly cited guideline is that commercial rent, including all NNN or CAM pass-throughs, should fall between 6% and 15% of gross revenue, depending on industry. Retail businesses that rely heavily on foot traffic and visibility often tolerate a higher occupancy cost ratio, while professional services and back-office operations typically aim to keep rent closer to the lower end of that range.
Why did my actual rent invoice come in higher than the quoted rate?
This usually happens when a tenant budgets only for the quoted base rate and forgets to add NNN, CAM, or other pass-through charges that are billed separately. A space quoted at $32 base plus $11 NNN per square foot is actually $43 per square foot all-in — nearly 35% higher than the headline number alone. Always calculate your full all-in cost, not just the base rate, before signing or budgeting against a lease.
This tool is for educational purposes only. Always verify important results with a qualified professional.
