Glossary · Leasing

Lease rollover

Also called Rollover, Lease expiration risk, Rollover risk.

Lease rollover is what happens when a lease expires: the tenant renews, or leaves and the space sits empty until a new tenant is found and fitted out. Modelling it means applying a renewal probability, downtime, leasing capital and a new market rent to every expiring lease.

Updated August 6, 2026 · All terms

How it works

In multifamily, rollover is a statistical event handled with a turnover rate, a few weeks of downtime and a modest make-ready cost. In office, retail and industrial it is the central risk in the asset, because a single lease can be a quarter of the building's income and its expiry can mean a year of vacancy and a seven-figure fit-out.

A proper rollover model runs each expiring lease through the same five assumptions: probability of renewal, downtime in months if the tenant leaves, market rent on the new lease, TI and commission at new-lease and renewal rates, and any free rent given. The expected outcome for that suite is the probability-weighted blend of the renew and the vacate case. Do it lease by lease, because averaging destroys the timing, and timing is what rollover risk is.

The pattern that deserves the most attention is clustering. A building where 60 percent of the income expires within an eighteen-month window carries a fundamentally different risk from one where the same 60 percent is spread across six years, even at identical WALT. Clustering is also what a refinance or a sale runs into: no lender prices a loan generously into a rollover cliff.

Worked example

Probability-weighting one expiring suite

Illustrative. 25,000 square feet expiring, 65 percent renewal probability. Renewal: $20 per square foot TI, 3 percent commission, no downtime. New lease: $65 per square foot TI, 6 percent commission, nine months downtime.

Renewal case leasing capitalTI $500,000 plus 3% commission$775,133
New-lease case leasing capitalTI $1,625,000 plus a 6% and 3% commission$2,027,552
New-lease case lost rent, nine months$600,000
Expected leasing capital65% of renewal plus 35% of new$1,213,480
Expected lost rent35% of $600,000$210,000
Expected cost of the rollover event$1,423,480

About $57 per square foot of expected cost on a single expiry. Move renewal probability from 65 percent to 50 percent and the expected cost rises by roughly $278,000, which is why that assumption should be evidenced by the tenant's history and its space needs, not chosen to make the deal work.

The common mistake

Modelling downtime without modelling the leasing capital that comes with it

Rollover is usually handled by applying a vacancy factor to the expiring space, which captures the lost rent and nothing else. The larger number is frequently the TI and commission required to fill it, which on office space can exceed two years of rent. A model with downtime and no leasing capital understates the cash cost of a roll by a wide margin, and it does so in the years where the property can least afford it. Every vacate case needs downtime, free rent, TI and commission attached to it.

Related terms

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