Where land becomes attached to or occupied alongside leased property, the legal position is often very different from what landlords and tenants expect. Under English law, land acquired by a tenant through “encroachment” can be dealt with in two ways, depending on whether the land is owned by a third party or by the landlord.
This is a specialised area of property law and the concepts that have evolved through caselaw are somewhat difficult to grasp. It is an issue that may not ever appear on a landlord or tenant’s radar, until a dispute arises. When it does arise, it can have significant consequences for development value, boundary positions, rent review discussions and, occasionally, ownership itself.
For landlords, tenants, developers and landowners, understanding the distinction between encroachment and accretion can avoid costly surprises.
What do lawyers mean by encroachment and accretion?
Although the two concepts are often discussed together, they cover slightly different situations.
Encroachment is an umbrella concept that applies when a leaseholder occupies property outside of the demise.
Encroachment can occur where a tenant takes possession of adjoining land that belongs to a third party (such as a neighbour) and was not included within the original demise (the property granted by the lease). This might happen intentionally, for example by moving a fence line, or gradually through long-term occupation of neighbouring land. In such cases, the freehold interest will usually pass to the landlord.
Conversely, when a tenant occupies an area outside of their leasehold interest but within the landlord’s demise then this land can be included within the tenant’s leasehold title and become subject to the terms of the lease through accretion.
The traditional rule: the tenant acquires it for the landlord
One of the most important principles is that a tenant who acquires additional land by encroaching onto neighbouring property is generally presumed to have done so for the benefit of their landlord.
That principle can appear counterintuitive. After all, the tenant may have maintained the land, fenced it, landscaped it and treated it as their own for many years. However, the courts have historically regarded the tenant’s occupation as arising from their position as tenant. The additional land is therefore treated as being held as an enlargement of the leased premises rather than as a separate, personal acquisition.
Key case law
One of the earliest authorities frequently cited in this area is Kingsmill v Millard (1855) 11 Ex 13. This case established the principle that where a tenant encroaches upon adjoining land during the term of a lease, the benefit of that encroachment is presumed to belong to the landlord rather than the tenant personally.
The leading modern authority is generally regarded as Smirk v Lyndale Developments Ltd [1975] Ch 317. The Court of Appeal confirmed that the law on this issue has “got into something of a tangle.” The court recognised that the precise outcome will depend on the facts. Questions of intention, possession, boundary arrangements and the terms of the lease can all be relevant. Whether or not the tenant takes possession of the land for the benefit of the landlord is a rebuttable presumption.
More recent, First Tier Tribunal caselaw (such as Relins v Gill [2025] UKFTT 00845 (PC)) has provided a helpful summary of the current position, particularly with regards accretion and the test to be applied.
Can a tenant ever acquire ownership of the additional land?
In some cases, a tenant may seek to establish rights through adverse possession, commonly known as “squatter’s rights”. However, adverse possession claims involving tenants are rarely straightforward.
A key difficulty is that occupation of the land may be treated as occupation on behalf of the landlord under the encroachment doctrine. If that analysis applies, the tenant may struggle to demonstrate the necessary independent intention to possess the land for their own benefit.
Why does this matter for property development?
Historically, encroachment disputes often arose in rural settings. Today, we see similar issues emerging in development projects, commercial estates and redevelopment schemes.
If a tenant has access to a loft space or a flat roof above their demise, then the tenant could theoretically acquire rights through accretion if they use the loft space as storage or the flat roof as a roof terrace or garden. That can impact on any future development plans that the landlord may have for the building.
If a developer takes a lease of a commercial site and during the project, land outside the lease boundary becomes enclosed within security fencing then years later similar discrepancies can arise.
At that point, seemingly minor boundary issues or title can have significant consequences, delaying transactions and causing planning and development complications. With land values remaining high across England and Wales, even relatively small strips of land can become commercially significant.
What should landlords do if they discover an encroachment?
Landlords should avoid assuming that an encroachment automatically increases the value of their title. The starting point should be a careful investigation of the lease plan and demise, physical boundary evidence, the identity of the adjoining owner and the history of occupation.
In many situations, an early professional assessment can prevent a relatively technical issue from escalating into a costly dispute.
What should tenants look out for?
Tenants often discover potential encroachments during lease renewals, rent reviews or redevelopment discussions. Where additional land has been occupied for a long period, it is worth understanding exactly why that occupation began and whether any formal rights exist.
Encroachment and accretion: old principles with modern relevance
Encroachment and accretion may sound like historical property law concepts best left in textbooks, but they continue to influence property disputes today. The central lesson is a simple one: occupation and ownership are not always the same thing. A tenant who acquires the use of additional land may not acquire the benefit of it personally, and landlords should not assume that every apparent boundary change automatically strengthens their title.
If you require legal support with any issues covered in this article, please contact Annabel Mayer or visit our website for more information: Personal Dispute Resolution Solicitors | Greene & Greene
This is only intended to be a summary and not specific legal advice.
