Yes — in most UK gardens, a shared boundary fence is usually fine for cat fencing on your side, as long as the setup is safe and does not weaken the fence.
HM Land Registry says title plans usually show only general boundaries, which is one reason fence ownership is often less clear-cut than people think.
Quick answer
If the fence is the normal boundary fence between your garden and the next one, that is usually a normal, workable setup for cat fencing. Readers should not treat a shared boundary fence like a problem by default.
The practical question is whether the system is fitted properly and whether the fence is sound enough to carry it. Planning Portal also says fences do not generally need building regulation approval, but they must still be structurally sound and maintained.
The left-side/right-side rule is a myth
A lot of people still think the fence on the left belongs to one house and the fence on the right belongs to the other. That is a myth.
HM Land Registry has explicitly called out “you always own the left (or right) side” as a common boundary myth, and says every property and boundary is different.
So for most readers, the better question is not “is this the left fence or the right fence?” It is simply: is this the normal boundary fence between the two gardens, or is it clearly sitting inside one property?
Shared fence vs clearly your neighbour’s fence
Keep it simple.
If the fence runs along the boundary between the two gardens, it is usually the normal boundary fence, so cat fencing on your side is often a practical, workable setup. If the fence is clearly your neighbour’s, ask first before attaching anything to it.
Does cat fencing need planning permission?
It can, depending on the system you use.
A lot of cat fencing systems add enough height to create planning issues. That is usually the real problem — not cat fencing itself, but the fact some systems push the overall fence too high.
Planning Portal says you usually do not need planning permission for a fence if it stays within the normal limits, and for most boundaries away from roads, the usual limit is 2 metres.
That is why the system matters. The Safe Whiskers Cat Fence is designed to stay below 2 metres, so for most standard garden boundaries it will typically avoid the planning issues that taller cat fence systems can create.
For the fuller explanation, read more here in our guide to cat fence planning permission in the UK.
You can also browse the full cat fence collection here.
Should you tell the neighbour?
Yes, as a courtesy.
A quick heads-up is usually the sensible approach, especially if the cat fence will be visible from their side. Citizens Advice says the best approach is usually to talk to your neighbour if there is a boundary issue.
That said, this should not be framed like a huge obstacle. For a normal shared boundary fence, it is usually just a straightforward garden improvement on your side.
What matters in practice
For most readers, the checklist is simple:
- the fence is the normal boundary fence
- the fence is in decent condition
- the cat-fencing system is fitted securely
- the setup does not make the fence unstable
- the overall height stays sensible for the garden
That is the practical standard readers should care about. Not left-versus-right myths. Not overcomplicating a normal shared fence. Just whether the setup is safe and properly installed.
Planning Portal says fences must still be structurally sound and maintained.
Bottom line
If it is the normal boundary fence between two UK gardens, cat fencing on your side is usually fine as long as the install is safe. The left-fence/right-fence rule is a myth, and the planning side often comes down to the overall height of the system you choose.
HM Land Registry and Planning Portal both point to the same practical conclusion: focus on the actual boundary setup and the overall height, not old garden folklore.
See the Safe Whiskers Cat Fence, browse the full cat fence collection, or read our guide to cat fence planning permission in the UK.