Rent Commencement Gap Calculator

Gap between possession and rent commencement costs the landlord carry.

Annual rent

Gap days

Carry rate %

Operating expenses PSF/yr

Rentable SF

Total gap cost

$221,980

Rent lost during gap

$157,808

OpEx owed by landlord

$59,178

How the math works

Gap fraction = days/365. Rent lost = annual × frac. OpEx owed = PSF × SF × frac. Carry charge on top. Sum for total cost.

$480k × 120/365 ≈ $158k rent lost. $12 × 15k × 33% ≈ $59k OpEx. Small carry. ~$220k total gap cost — significant concession.

Editorial noteMaintained by EveryCalc - Reviewed June 2026

EveryCalc calculators are designed for fast, practical estimates with transparent inputs and no required account. We use plain formulas, visible assumptions, and related tools so visitors can check the result from more than one angle.

Results are informational only. For financial, tax, legal, medical, construction, or other high-impact decisions, verify the output against primary sources or a qualified professional.

Learn more about our review process on the EveryCalc methodology page.

How this calculator works

What this page estimates

This Rent Commencement Gap Calculator is built to give a quick, browser-based estimate for rent commencement gap. Gap between possession and rent commencement costs the landlord carry. The inputs stay on the page during normal use, and the result should be treated as an estimate for planning, comparison, or education rather than professional advice.

Calculation approach

The calculator applies the standard relationship implied by the inputs, then formats the answer so it can be checked and reused. For finance tools, the most important step is using consistent units, rates, time periods, and assumptions before comparing the result with another calculator or outside quote.

Example workflow

For example, start with a realistic value you already know, change one input at a time, and watch how the answer moves. That makes it easier to tell whether the result is being driven by the main amount, the rate, the time period, or a unit conversion.

Practical checks

Use current, real-world numbers when the result affects money, health, tax, or legal decisions.
Run a low, base, and high case when the inputs are estimates.
Check the related calculators below when the next decision depends on a different assumption.

How to interpret the rent commencement gap result

Best use

Use the result as a planning number for comparing payments, rates, returns, tax reserves, or cash-flow choices before you request a quote or make a commitment.

Cross-check

Compare the answer with the contract, lender estimate, tax form, brokerage statement, payroll record, or invoice that will control the real-world outcome.

Watch for

Do not rely on a single optimistic rate, return, or fee assumption. Money pages work best when you run low, base, and high cases and keep professional advice separate from the estimate.

This page belongs to the Finance calculator library, so the answer should be read in the context of the decision you are modeling rather than as a universal rule.

Before relying on this rent commencement gap estimate

Most calculator mistakes come from the inputs, not the arithmetic. Use this short audit before you reuse the answer in a spreadsheet, quote, application, or important conversation.

Confirm source numbers

Match balances, rates, fees, taxes, income, and payment dates against the lender quote, payroll record, tax form, statement, invoice, or contract.

Separate cash flow from total cost

A lower monthly payment can still cost more over time if fees, interest, taxes, or a longer term are hidden in the structure.

Run conservative cases

Test at least one higher-cost or lower-return case before using the output for a purchase, refinance, investment, loan, or tax decision.

Rerun this page when the rate, price, term, fee, tax rule, income, expense, or expected holding period changes.

How to Use

Enter annual rent.
Enter gap days.
Enter carry rate %.
Enter operating expenses owed by landlord PSF.
Enter SF.
Read gap cost to landlord.

Frequently Asked Questions

Why does the gap exist?

Tenants negotiate a rent-free period after possession for build-out, typically 60-180 days. Landlord carries debt service, property taxes, insurance, utilities with no rent coming in. Explicit in lease to avoid ambiguity vs 'free rent' for negotiation.

How big should gap be?

Depends on TI complexity. Turn-key shell: 30-60 days. Full build-out office or retail: 90-180 days. Restaurant/complex use: 180-365 days. Landlord tries to shorten; tenant tries to lengthen to avoid paying rent during unproductive period.

Accelerate commencement?

Commencement triggers: substantial completion of LL's work, CO issuance, fixed outside date. Landlord prefers outside date to force tenant to accelerate. Tenant prefers substantial completion with mutual signoff. Hybrid triggers common in major deals.