Boundary demarcation agreements - what do you need to know?

A boundary demarcation agreement is generally a written agreement between two property owners that sets out the physical boundary between their properties.

Such an agreement can include details of who is responsible for maintaining and retaining features such as walls and fences. It is often used by property owners to resolve disputes about the position of legal boundary lines and can be registered with the HM Land Registry.

How would I know if my property is affected by a boundary agreement?

If a boundary agreement is registered on a title, it is usually obvious because the agreement is referenced on the registered title, even if the full text of the agreement is not included on the title. The Land Registry should be able to supply a copy of any agreement that has been submitted to them and which they have noted on the title.

Can boundary agreements still apply to new owners if unregistered?

This is an interesting question, and the Court of Appeal has clarified it very recently. The issue is examined in the case of White v Alder [2025] EWCA CIB392.

The boundary dispute arose between Mr White's property, Willow Cottage, and the neighbouring property, The Old Stores, which was owned by Mr and Mrs Alder.

Before their purchase and unknown to Mr White and the Alders, the previous owners had entered into an oral boundary demarcation agreement, agreeing on the boundary between the properties, which was later recorded in writing.

In 2016, Mr White demolished part of his boundary wall and began building an extension to Willow Cottage. The Alders then alleged that Mr White had trespassed on their land and proceedings were issued in 2020 for a declaration as to the true position of the boundary. The Court determined that the boundary agreement bound both Mr White and the Alders.

Therefore, Mr White appealed to the Court of Appeal to overturn the ruling that he was bound by a boundary agreement that he knew nothing about when he bought his property.

In a somewhat surprising decision, the Court of Appeal upheld the lower Court's decision, which means that it is now good law that a boundary demarcation agreement is binding on successors in title even if they did not know about it.

The Court did make a distinction between various types of boundary agreement. If you have a boundary agreement that transfers land from one neighbour to another, that does not necessarily bind a successor in title. However, if you have an agreement that simply defines unclear boundaries and involves a trivial land transfer of a very nominal amount, then that would bind a successor in title, even if they knew nothing about it when they were buying the property.

What should be included in a boundary agreement?

• Names and addresses for each property owner
• Date when agreement became effective
• Boundary description, ideally accompanied by a plan
• Signatures from both property owners

Does a boundary agreement actually transfer ownership of land?

No. If land is being transferred then a formal transfer document is needed.

Is a boundary agreement the same as a determined boundary?

No. Boundary agreements are based on a mutual agreement between property owners and are straightforward documents. A determined boundary is a legally binding delineation of the exact boundary line, which is often done if a dispute arises.

You can apply to the Land Registry to determine a boundary, or submit a detailed plan prepared by a chartered surveyor, which the Land Registry will then serve on the other land owner and ask them to agree. In order to apply to the Land Registry for a determined boundary, you may need to provide supporting evidence such as deeds or expert reports.

You will need to complete an application form and pay the requisite fees to the Land Registry. A determined boundary requires a great deal of precision and specificity within 10 millimetres.