Lease Event Concentration Risk: when too much income depends on the same period
By Doug Parker, Montbart
First published 28th July 2026
A lot of what I look at in commercial property centres around risk. The majority of properties are held by individuals, companies and authorities as a means to exchange a capital sum in exchange for a regular income. In short – investment. And one of the most critical aspects of investment, is an understanding of risk.
A multi-let commercial property can appear well diversified on the surface. There may be several tenants, several leases and several separate income streams. So on the face of it, this should reduce the owner’s risk exposure to a dramatic disruption of their investment return (i.e. commercial rent).
The number of tenants though, doesn’t tell the whole story. If a significant proportion of the rental income is threatened by lease break options or lease expiries within the same relatively short period, the property may carry a substantial concentration of risk.
The building might be fully occupied today, yet still face the possibility of several tenants making decisions about their future plans at broadly the same time. I refer to this as Lease Event Concentration Risk.
It is the risk that too much rental income, asset value and management effort becomes exposed in the same narrow timeframe. And that concentration can affect much more than occupancy. It can influence refinancing, selling, capital expenditure, tenant negotiations and the general level of control the owner has over their investment.
Occupancy is only part of the picture
A property’s current occupancy level is an important and well-used measure, but it only tells of how full the building is today. The lease profile provides a good indication of how secure that income might be tomorrow.
A fully occupied building can still have a weak lease profile. As an example, several tenants might have break options within the next eighteen months. Others may be approaching lease expiry shortly afterwards. The annual rent may appear strong, but a large proportion of it may have limited term certain.
The risk is not necessarily that every tenant will leave; the risk is that too many tenants are being given the opportunity to reconsider their occupation at the same time. Even where only one or two actually vacate the building, the owner could face a period of uncertainty involving multiple negotiations, possible refurbishments and decisions over how much capital to commit to the asset. That is very different from managing a single lease event in isolation.
Breaks and expiries create different risks
Lease break options and lease expiries are not the same, and they shouldn’t be treated as though they are. A lease expiry is a known end date, and unless a renewal or new lease is agreed, the existing contractual term will come to an end (subject to any statutory rights or other legal arrangements that might apply).
A break option creates uncertainty though. The tenant may exercise it, or choose not to exercise it, use it as part of a wider negotiation tactic or serve a notice that later becomes disputed.
There are also likely to be conditions attached to the break. These might relate to the payment of rent, occupation, compliance with particular obligations or the service of notice in a strict form and within a specific timetable.
From an asset-management perspective, however, both breaks and expiries create a ‘decision horizon’. They both mark points at which either the tenant, the landlord or both must decide whether the existing arrangement is to continue. It’s a mistake is to assume that the important date is the break date or expiry itself, and in reality the critical decision-making should begin much earlier.
A tenant considering future plans may already be looking at:
Is the space still suitable?
Likely staffing levels and working practices.
Any alternative buildings that might offer more (for less?)
Anticipated relocation costs.
New fit-out requirements.
Energy performance of current space.
Ongoing access, parking and transport.
Future contractual liability (how long do they need the lease term to be?)
And the operational disruption (pain) of moving.
So by the time a formal notice is served, much of the tenant’s thinking has probably already have taken place. An owner who waits for some certainty, may very well be starting the conversation long after the tenant has already made up their mind.
Several tenants do not always create diversification
A multi-let property is often regarded as less risky than a single-let property because the income is spread across several occupiers. And that can be true, however several tenants do not automatically create genuine diversification if their lease events are concentrated within the same period.
The building might have ten occupiers, but if five of them represent sixty per cent of the rent and all have breaks or expiries within eighteen months, the income risk remains heavily concentrated. The same principle can apply across a wider portfolio; several assets may appear independent, but contain leases that expose the owner to the very same timing risk.
The concentration may be particularly significant where:
Several major tenants have lease events in the same year;
A high proportion of total rent is dependent upon these major tenants.
Similar units could come back to the market simultaneously.
Substantial capital expenditure might be needed across several newly vacated units
Or local market demand is dependent upon the same limited group of occupiers.
It can create an illusion of stability, and the income statement shows the properties are fully occupied. The lease profile shows how quickly that position could change though.
Lease Event Concentration Risk is related to, but distinct from, the weighted average unexpired lease term, commonly referred to as WAULT.
WAULT provides a handy measure of the average remaining lease term, usually weighted by rental income. It can offer a broad indication of income duration and is increasingly used when considering the strength of an investment’s lease profile. However, an average doesn’t necessarily show how the underlying lease events are distributed.
Two properties may have the same WAULT but carry significantly different risk profiles. One may have lease events spread relatively evenly over several years. The other may have a substantial proportion of its income exposed within a few months. WAULT measures average duration, and Lease Event Concentration Risk establishes the pattern beneath that average.
Why lease events begin affecting value early
The financial effect of a lease event does not land on the day a tenant leaves, it can affect an asset well before the break or expiry date arrives. A prospective purchaser will usually want to understand how much of the existing income is secure and for how long. A lender will consider the level of rent at risk during the period of a loan, and a valuer might look at the likelihood of vacancy, lease incentives, refurbishment costs and the likely amount of time to secure replacement income. So the headline rent roll is really only part of the picture.
An owner might receive £500,000 per year from a building, but if a large proportion of that income is exposed to near-term lease events, the market might place less weight on it than the headline figure suggests. Term certain really matters, because rental income that is contractually secured for a significant period can offer better confidence than income that could end abruptly within months. This doesn’t mean short leases or break options are undesirable. They offer vital flexibility, offer opportunities for rental growth or allow the owner to reposition the building. The risk must be understood though.
A short lease may be entirely consistent with the owner’s strategy, but several short leases ending together may be something else entirely.
Tenant retention is usually less costly than replacement
There is a familiar principle in business that retaining an existing customer is generally easier and less expensive than finding a new one. The same principle applies to commercial property. Retaining a ‘good’ existing tenant can avoid many of the costs and uncertainties associated with vacancy and reletting.
When a tenant leaves, the owner is likely to face:
A period without rent (a rent void).
A continued liability for business rates,
Ongoing insurance and security costs,
Utilities and compliance costs,
Dilapidations negotiations,
Refurbishment, upgrades or reinstatement works,
Agency and marketing fees,
Legal costs,
Tenant lease incentives,
Fit-out periods,
The risk that the market has weakened.
Even after a new letting is agreed, the replacement income probably won’t begin immediately. The incoming tenant might expect a rent-free period, works may be needed before occupation, and the legal process may take longer than expected. So an apparently small gap between one lease ending and another beginning can become an expensive period of lost income and additional cost. So tenant retention certainly deserves early attention.
Sometimes… the tenant can be allowed to leave
Notwithstanding the above commentary, there will be occasions when the premises no longer work for the tenant. The business might have grown, contracted or just changed the way it operates. The location might no longer work for its customers or workforce, or the building may not meet future energy, accessibility or technical requirements any more.
There might also be circumstances where the existing lease structure and agreement simply doesn’t work for the landlord. The tenant might occupy the space inefficiently, pay a rent significantly below market level or prevent a wider refurbishment, redevelopment or repositioning of the asset. And in these situations, an orderly vacation might be better than forcing a renewal that neither party really wants.
The purpose of early engagement is not to prevent every tenant from leaving, it’s rather to understand the tenant’s intentions soon enough for the owner to respond. This might mean negotiating a lease extension, varying the space occupied, offering a planned refurbishment or just agreeing a managed exit and beginning the search for a replacement occupier early. This is all about reducing the chance of unpleasant surprises.
The value of early tenant engagement
Tenant conversations are sometimes put-off or avoided because owners are concerned that raising the subject will encourage the tenant to leave or create some opportunity to seek concessions to stay. To some degree, this is understandable because a badly handled conversation might weaken the owner’s position. Avoiding the subject does not remove the risk though, it just reduces the time available to respond.
Early engagement is worthwhile to help the owner understand:
Whether the tenant intends to stay,
Whether the current space is still suitable,
What considerations might influence the decision,
Whether alterations or investment might influence the tenant staying
Whether the tenant needs more or less space,
How realistic any proposed renewal terms might be.
Of course, the tenant might not offer a certain answer straight away, but even an idea of their likely intentions can improve planning. It can help the owner establish which lease events need immediate attention, which tenants are likely to renew and which areas might need to be prepared for the market. The greater the concentration of lease events, the more valuable this early information becomes.
When several negotiations happen all at once
Managing a single lease event well takes time, and usually involves lease review, assessment of market rent, understanding the tenant’s position, inspecting the premises, considering refurbishment options and actually agreeing the deal. When several lease events occur at the same time though, those demands multiply.
The owner may find themselves dealing simultaneously with a combination of renewal negotiations, break notices, rent reviews, dilapidations, refurbishment decisions, marketing campaigns, legal documents and internal funding approvals.
So it’s clear the risk is not only financial, it’s also operational. Capacity to manage everything becomes stretched, decisions might be made reactively, and the most urgent issue gets attention rather than the most important one.
A landlord with a single upcoming expiry can look at it tactically, but a landlord with six lease events in the same quarter might find themselves struggling to manage each one effectively. This is another reason the concentration of lease events matters, it reduces the owner’s ability to manage each event with the care it deserves.
Lease events and capital expenditure
When a tenant departs, this often triggers capital expenditure (capex) on the property. The space is likely to need to be returned to a lettable condition, upgraded to meet current market expectations or maybe adapted for a different type of occupier. Where several tenants leave within the same period though, those costs can arrive together.
Capex might come in the form of repairs and reinstatement, mechanical and electrical upgrades, decoration and flooring replacement, energy-efficiency/compliance improvements, subdivision or amalgamation or improvements to common areas.
Even where some costs are recoverable through dilapidations, there can often be delays, disputes and significant differences between the amount claimed and the amount ultimately received. So it’s possible the owner will need to finance the works before settlement of the claim. Therefore lease concentration can also become capital expenditure concentration.
The risk might be even more acute if the owner has not put adequate funds aside, can’t easily access more borrowing or intends to refinance at around the same time. A full building can hide a future cash-flow problem that hasn’t yet appeared in the accounts.
Lease regears as value protection
A lease regear is often looked upon simply as a leasing transaction, but in practice, it can also be value protection. If a suitable tenant is willing to commit to a longer term, an early lease extension may improve certainty of income. This might support a future sale, refinancing, a stronger valuation figure and easier scheduling of planned works.
This doesn’t mean every tenant should be offered an extension on favourable terms though. It’s still important for the landlord/owner to consider ‘market’ rent, lease incentives, break rights, covenant strength, repairing obligations and (of course) the wider asset strategy.
Where several lease events are concentrated, selective lease regears may also help stagger the profile. It’s more than simply an administrative exercise, it can remove an area of uncertainty from the investment. The owner may not be able to eliminate every concentration of risk, but it may be able to reduce the number of major decisions falling within the same period.
Measuring the risk properly
A lease events schedule is a very useful starting point, but dates alone don’t show the full risk exposure. It’s important to also consider the proportion of income attached to each event. For example a single lease break affecting a small storage unit is not equivalent to an expiry involving the largest tenant in the building.
An income-weighted lease profile review can pinpoint where the real risk is. Likely metrics might vary, but as examples the following might be included:
annual rent at risk (as an amount);
income exposed (as a percentage of the whole)
Size (area) and configuration of the space
The potential demand for reletting
Estimated costs to refurbish
Expected lease incentive package
Expected void period
The importance of the tenant to the wider building.
Lease Event Concentration Risk can also be measured. At its simplest, an owner can look at the proportion of passing rent subject to tenant breaks or lease expiries within a defined period. A more developed model could also assess how tightly those events are clustered, how soon they occur and the relative significance of the income involved.
This creates a different perspective from WAULT. Instead of looking at average lease term remaining, it establishes how much income may be at risk at the same time.
The detailed methodology is for separate consideration (and a different article). The important first step though is recognising that a stable average can still conceal an uneven and potentially risky distribution of lease events. Several minor events may be manageable, but a couple of major events involving half the building’s income is likely to be a different matter.
Scenario planning
Lease concentration risk can’t be removed just by predicting which tenants will stay. Tenants’ plans can change quickly, markets can be unpredictable, and businesses are acquired, shrink or fail. The property market can be a lawless place sometimes.
A somewhat useful approach is to consider several plausible scenarios such as -what happens if every tenant renews? What happens if the largest tenant leaves? What level of capex would be needed? Could the building still meet lending covenants? Would part of the property need to be reconfigured?
We’re not looking to attempt to forecast the future, but we do need to understand how to respond if a less-than-favourable outcome took place. It turns a calendar of dates into a management tool and allows owners to make decisions while they still have options.
Reducing Lease Event Concentration Risk
Of course it’s not possible or desirable to eliminate lease events, but every commercial lease will eventually reach a point of decision. It’s therefore critical to manage the risk to income and value over a short period of time with a clear plan.
As a checklist, it might be useful to look at:
Maintaining an accurate lease-events register
Reviewing events at least eighteen to twenty-four months ahead
Weighting events by income and strategic importance
Speaking to key tenants comfortably before formal notice periods
Looking at priority lease regears
Planning refurbishment and dilapidations strategies early
Working to stagger future lease expiries where commercially possible
Modelling void, lease incentive and capital expenditure
Reviewing the effect on lending/valuation and refinancing
Making sure the owner has management capacity to deal with the likely workload.
The above will obviously vary between assets, and some buildings might benefit from longer lease commitments and a more evenly spread expiry profile. On the other hand, sometimes it is worthwhile to maintain some flexibility if the owner intends to refurbish, redevelop or sell (this is a big commitment to those plans though). It’s important the profile aligns with the strategy rather than arising by accident.
First published by Montbart Limited on 28th July 2026
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