How to Install a Letterbox Into a PVC Fence?

If you're upgrading your yard with the stylish and durable fencing style of PVC fencing, adding a built-in letterbox can be the perfect finishing touch. Installing a letterbox directly into your PVC fence panels keeps everything neat, functional and modern – no separate post or freestanding mailbox is required.

PVC fencing has become an increasingly popular fencing material in Australia thanks to its strength, durability and low-maintenance appeal. It’s also highly adaptable – one of the many differences between PVC and timber fencing, is that PVC is easier to cut and drill than timber or metal, and it resists cracking or splintering, which is exactly what makes installing a mailbox into a PVC fence both practical and achievable for DIYers.

Outback Fencing, as well as being a trusted supplier of premium fencing materials, also has a team experienced in fencing installation. In this step-by-step video and guide below, we’ll show you how to install a letterbox into PVC fencing using simple tools and straightforward techniques to achieve a clean and professional-looking result.

Tools and Materials You'll Need

To successfully install your letterbox, have these tools and parts ready:

• PVC fence letterbox kit (with front and rear plates)
• Tape measure
• Pencil or permanent marker
• Spirit level
• Angle grinder or jigsaw (with a plastic/PVC-compatible blade)
• Drill & drill bits
• Screws (white or stainless steel preferred)
• Screwdriver or impact driver
• Optional: Masking tape (for clean marking) and a second person for assistance

Most modern letterbox kits are designed to fit flush against a panel and clamp together from both sides, making them ideal for use with PVC fencing.

How to Install a Letterbox into a PVC Fence: Step-by-Step?

Step 1: Find the Best Location for the Letterbox

Before cutting anything, decide where on your fence the mailbox will go. If you’ve already installed a PVC gate, you can cut and insert your PVC letterbox right next to it. So, you want it near the gate, but it’s important to also get a feel of what height and distance from the gate you want it installed. Here are a few key tips:

• Accessibility – is it easy for the postie to reach without stepping into your yard? If you have designed with garden plants in front of your fence, choose an area where plants aren’t in the way.
• Height – the standard installation height is around 1000–1200mm from the ground for letterboxes, making it easy to reach with your hands.
• Panel placement – you’ll want to choose a solid section of the PVC fence panel, ideally close to a post for added support.

Once you’ve selected the spot, it’s time to measure the cutout.

Step 2: Measure the Letterbox Insert Area

To install your letterbox, you need to cut a hole straight and through the PVC fence panel. You’ll be cutting an opening for the inner box of the letterbox – not the flange that sits on the front. This is critical for a snug and secure fit that elevates your front garden design.

So, first, measure the width and height of the internal box (not the faceplate), and then add 1 to 2mm of extra space to allow for easy fitting and adjustments. You can use a pencil and a level to mark your rectangle directly onto the PVC fence panel.

For example, if your insert box measures 175mm x 355mm, mark those dimensions exactly and double-check that everything is straight. Also, a great tip is to use masking tape around the cutting area, which can help you draw cleaner lines and reduce scratches from the angle grinder.

Step 3: Cut the Opening in the PVC Fence Panel

Now that your guide is marked, it's time to cut the opening – the permanent part, so make sure everything is marked out correctly. But don’t worry, one thing to know about PVC fencing is that it’s typically easy and smooth to cut through to make panels fit or install things like letterboxes.

Make the cut by using an angle grinder or jigsaw with a fine-toothed blade suitable for cutting PVC and cut slowly and carefully to avoid melting or chipping. Stay slightly outside the line to avoid having to expand the hole (it’s harder to cut small sections off), and the letterbox flange will hide minor imperfections anyway.

After cutting the front, go to the back of the fence and cut through any parts you missed. Then push the cut-out part of the panel out.

Once cut, double-check that the letterbox insert fits inside the hole before moving on. The front flange and rear backing plate are designed to cover rough edges, so don’t worry if the cut isn’t perfectly smooth.

Step 4: Install the Letterbox

With your hole cut, it’s time to install your PVC letterbox. Start by inserting the letterbox from the front of the PVC fence panel, making sure the faceplate sits flush and evenly against the panel. From the back side, attach the rear clamping plate, pulling the letterbox back and the clamping plate forward so it sits tight. Line everything up and make sure it’s level. This part is easier with a second person – one holding the front in place while the other secures the back.

Now it's time to fasten the letterbox in place. A great fence maintenance tip is to ensure a tight and secure installation, as it will drastically minimise future work. Start by drilling small pilot holes in the screw locations that connect with the fence panel to avoid cracking the PVC. Use the screws supplied with the mailbox kit, or swap them with white-painted steel screws for a more secure and weather-resistant hold.

As well as screwing the clamp plate into the panels, you can also screen the plate into the sides of the letterbox insert. Place screws in the corners of the front and back plates to clamp the mailbox snugly. Give it a final, gentle shake to make sure the box is firmly secured and doesn't wobble. This not only helps the letterbox live a long, sturdy life, but the PVC fencing remains structurally sound and weatherproof and prevents you from having to repair a broken fence in the process of installing your letterbox.

Packing Up

Before finishing up, test the lock and key to confirm functionality. Then, clean up PVC dust and wipe down any markings from the fencing panel – you can check our guide on how to clean and maintain a PVC fence for everything you need to protect the quality and look of your fence. And that’s it – your mailbox is now professionally integrated into your PVC fence! By installing it yourself, you’ve saved yourself on labour costs and (possibly) learnt a new skill that can go a long way in helping your future garden design budgeting.

PVC fencing is an advanced material that homeowners love for its low-maintenance, high-impact. And adding a letterbox to your front fencing is the perfect finishing touch for this innovative material to really boost the value of your rural home. For any support with your installations or if you need any help sourcing and selecting the right fencing materials for you, feel free to get in touch with the team at Outback Fencing, and we’d love to help you find solutions.