Commercial Lease Calculator

Last updated: March 18, 2026
Reviewed by: LumoCalculator Team

Estimate occupancy cost as base rent plus tenant-paid operating expenses, then review effective rent per SF, move-in cash, and multi-year escalation impact for one lease structure.

Lease Inputs

Quick Scenarios

Lease structure

Space and rent

$
%

Operating expenses per SF per year

$
$
$
$

Concessions and move-in cash

$

Lease Cost Summary

Year 1 occupancy cost

$93,000

2,000 SF - Triple Net (NNN)

Effective rent per SF

$46.50

Tenant-paid operating expenses

$33,000

35.5% of year-one cost

Total lease value

$493,750

Final-year occupancy cost

$104,672

Move-in cash estimate

-$26,750

Security deposit

$15,500

TI allowance

$50,000

Summary

This Triple Net (NNN) scenario lands at $93,000 in year-one occupancy cost, or $46.50 per SF, with taxes, insurance, CAM, and utilities carrying 35.5% of the year-one total.

Tenant-paid operating expenses make up 35.5% of the year-one occupancy cost, and the modeled final-year total reaches $104,672. Comparing base rent alone would understate the true commitment.

Detailed Breakdown

MetricValue
Square footage2,000 SF
Lease typeTriple Net (NNN)
Base rent per SF$30.00 / SF
Year 1 base rent$60,000
Property tax$8,000
Insurance$3,000
CAM$16,000
Utilities$6,000
Year 1 occupancy cost$93,000
Monthly occupancy cost$7,750
Operating expense share35.5%
Security deposit$15,500
TI allowance$50,000
Move-in cash estimate-$26,750
Escalation assumption3.0%
Final-year cost$104,672
Total escalation cost$28,750
Total lease value$493,750

Current Calculation Check

Year 1 occupancy cost

Year 1 occupancy cost = Base rent + Tenant-paid operating expenses

Year 1 occupancy cost = $60,000 + $33,000 = $93,000

Effective rent check

Effective rent per SF = Year 1 occupancy cost / square footage

Effective rent per SF = $93,000 / 2,000 = $46.50 per SF

Move-in cash check

Move-in cash = First month occupancy cost + Security deposit - TI allowance

Move-in cash = $7,750 + $15,500 - $50,000 = -$26,750

Scenario highlights

  • Year-one occupancy cost: $93,000.
  • Effective rent: $46.50 per SF.
  • Move-in cash estimate: -$26,750.
  • Tenant-paid operating expenses account for 35.5% of year-one cost.

Year-by-Year Lease Schedule

YearBase rentOperating expensesTotal occupancy costMonthly costEffective rent / SFCumulative total
1$60,000$33,000$93,000$7,750$46.50$93,000
2$61,800$33,990$95,790$7,983$47.90$188,790
3$63,654$35,010$98,664$8,222$49.33$287,454
4$65,564$36,060$101,624$8,469$50.81$389,077
5$67,531$37,142$104,672$8,723$52.34$493,750
The calculator assumes the same escalation rate applies to both base rent and tenant-paid operating expenses.
TI allowance is treated as an upfront offset, not as an amortized landlord contribution spread through rent.
Security deposit is estimated from the modeled year-one monthly occupancy cost rather than from a custom legal clause.

Editorial & Review Information

Reviewed on: 2026-03-18

Published on: 2025-12-04

Author: LumoCalculator Editorial Team

What we checked: Occupancy-cost math, lease-type assumptions, example arithmetic, scope boundaries, and source accessibility.

Purpose and scope: This page supports lease comparison and planning. It is not legal advice and not a substitute for the signed clause that governs expense stops, free rent, TI disbursement, or percentage-rent treatment.

How to use this review: Keep rentable SF, expense assumptions, concessions, and escalation logic consistent across offers before comparing effective rent or move-in cash.

Use Scenarios

Site selection and LOI review

Normalize gross and NNN quotes into the same year-one occupancy cost before choosing which location deserves deeper legal review.

Budget and cash planning

Estimate deposit, TI offset, and escalated occupancy cost before signing a lease that will pressure working capital in later years.

Revenue needed to carry occupancy

Once lease cost is clear, compare it with the Break-Even Calculator to estimate how much gross profit or sales volume the location must support.

Formula Explanation

1) Base rent

Annual base rent = Rentable SF x Base rent per SF

This converts the quoted rental rate into a full-year cost on the rentable-square-foot basis used in the lease.

2) Tenant-paid operating expenses

Operating expenses = Taxes + Insurance + CAM + Utilities

The included line items depend on the lease structure. Gross leases usually leave these with the landlord, modified gross often pushes CAM and utilities to the tenant, and NNN pushes all four categories to the tenant.

3) Effective rent and total occupancy cost

Year 1 occupancy cost = Base rent + Tenant-paid operating expenses

Effective rent per SF = Year 1 occupancy cost / Rentable SF

This is the apples-to-apples comparison view that turns mixed rent and expense structures into one comparable unit cost.

4) Multi-year lease value and move-in cash

Each future year = Prior year x (1 + escalation rate)

Move-in cash = First month occupancy cost + Security deposit - TI allowance

The model uses one escalation rate for both rent and tenant-paid operating expenses, then estimates the front-loaded cash impact from the first month, deposit, and TI offset.

How to Read the Result

Gross lease read

A higher base quote may still be competitive because most operating expenses are already embedded. Focus on what is excluded from the gross structure before comparing it with an NNN offer.

Modified gross read

Shared expense structures often look balanced, but CAM and utilities can still move the effective rate enough to change which suite is really cheaper.

NNN read

A low base rate can hide a large pass-through burden. Watch the operating-expense share, escalation effect, and audit language before treating the location as the lowest-cost option.

Typical NNN Ranges by Property Type

Property typeProperty taxInsuranceCAMTotal NNN
Office$3-$6/SF$1-$2/SF$6-$12/SF$10-$20/SF
Retail$4-$8/SF$1-$2/SF$8-$15/SF$13-$25/SF
Industrial$1-$3/SF$0.50-$1/SF$1-$3/SF$2.50-$7/SF
Medical$4-$7/SF$1-$2/SF$10-$18/SF$15-$27/SF

Important Lease Clauses to Negotiate

CAM cap

Limits annual growth in controllable common-area charges.

Base-year stop

Landlord covers expenses up to a stated base-year level and tenant pays increases above it.

Audit rights

Lets the tenant review reconciliations and challenge unsupported expense pass-throughs.

Renewal option

Preserves leverage if the location works and relocation cost would be high.

Exclusive use

Prevents the landlord from placing a direct competitor too close to the same trade area.

HVAC or after-hours language

Clarifies whether extended-hours service is bundled or separately billed.

Example Cases

Case 1: Gross office relocation

Inputs

  • Lease type: Full Service Gross
  • Square footage: 1,800 SF
  • Base rent: $38.00 per SF
  • Term: 5 years
  • Escalation: 3.0%

Computed Results

  • Year 1 occupancy cost: $68,400
  • Effective rent: $38.00 per SF
  • Total lease value: $363,145
  • Move-in cash: -$13,200

Interpretation

The gross quote keeps budgeting simple, but the tenant still needs to decide whether the higher base rate is cheaper than an NNN alternative once pass-through costs are normalized.

Decision Hint

Use the same rentable SF and same concession treatment before comparing this with a lower quoted NNN rate.

Case 2: Retail NNN storefront

Inputs

  • Lease type: Triple Net (NNN)
  • Square footage: 2,500 SF
  • Base rent: $34.00 per SF
  • Term: 7 years
  • Escalation: 3.0%

Computed Results

  • Year 1 occupancy cost: $128,750
  • Effective rent: $51.50 per SF
  • Total lease value: $986,542
  • Move-in cash: -$7,083

Interpretation

The base rent looks manageable, but the real occupancy commitment changes once taxes, insurance, CAM, and utilities are added and escalated.

Decision Hint

Negotiate CAM caps, audit rights, and exclusions before assuming the year-one pass-through estimate will stay stable.

Case 3: Modified-gross medical suite

Inputs

  • Lease type: Modified Gross
  • Square footage: 3,000 SF
  • Base rent: $41.00 per SF
  • Term: 7 years
  • Escalation: 2.5%

Computed Results

  • Year 1 occupancy cost: $163,500
  • Effective rent: $54.50 per SF
  • Total lease value: $1,234,005
  • Move-in cash: -$50,500

Interpretation

Modified gross can look balanced, but CAM and utility assumptions still move the effective rate enough to change the ranking between similar suites.

Decision Hint

Stress-test longer clinic hours, HVAC needs, and shared-area reconciliations before treating this as a fixed-cost structure.

Boundary Conditions

Use rentable square footage throughout the comparison. Mixing usable and rentable SF will distort the effective rate.
This page applies one escalation rate to both rent and tenant-paid operating expenses. Real leases can escalate those items differently.
Percentage rent, free rent, parking, broker commissions, and separate legal reimbursements are outside scope and should be layered in manually if they matter.
TI allowance is modeled as an upfront offset. If the landlord reimburses after completion or amortizes TI through rent, adjust the cash view accordingly.
Security deposit is estimated from the modeled year-one monthly occupancy cost, but the signed lease may define deposit on a different rent basis.
If renewal notice timing matters more than occupancy math, pair this page with the Contract Date Calculator after the business terms are known.

Sources & References

Frequently Asked Questions

How does this commercial lease calculator work?
The calculator builds year-one occupancy cost from rentable square footage times base rent plus any tenant-paid operating expenses in the selected lease structure. It then applies the same escalation assumption across the full term to estimate total lease value, final-year cost, and move-in cash.
What is effective rent per SF?
Effective rent per SF is the modeled year-one occupancy cost divided by the rentable square footage. It is the easiest way to compare one offer with another because it keeps base rent and tenant-paid pass-through expenses in the same denominator.
What is the difference between gross, modified gross, and NNN leases?
A gross lease usually wraps most operating expenses into the quoted rent. A modified gross lease often leaves CAM and utilities with the tenant while taxes and insurance stay with the landlord. A triple-net lease shifts taxes, insurance, CAM, and utilities to the tenant, so the base rate alone is not the full occupancy cost.
How does TI allowance affect move-in cash?
This page treats TI allowance as an upfront offset against first-month occupancy cost plus the estimated security deposit. Real leases may reimburse TI after work is completed or may amortize it through rent, so confirm the disbursement clause before treating the modeled move-in cash as final.
Why can the final-year cost be much higher than the first-year quote?
The model escalates both base rent and tenant-paid operating expenses at the annual rate you enter. That means a quote that looks manageable in year one can produce a noticeably higher occupancy burden by the end of the term if expenses and rent both step up every year.
What does this calculator not model?
It does not model percentage rent, free-rent periods, base-year stops, parking charges, after-hours HVAC fees, broker commissions, capital-repair carve-outs, or a separate escalation rule for taxes and CAM. Use those clauses as a manual adjustment after reviewing the baseline occupancy cost here.
How should I compare two lease offers?
Keep the same rentable-square-foot basis, expense assumptions, escalation rate, and concession treatment across both scenarios. Then compare effective rent per SF, move-in cash, total lease value, and the share of occupancy cost coming from pass-through expenses instead of comparing base rent alone.