Filler Panels, End Panels and Plinths for Kitchen Units: What They Are and How They Fit

Kitchen units are manufactured in standard sizes. Walls, floors, and ceilings are not. The panels and boards that bridge the gaps between standard cabinet sizes and real room geometry are filler panels, end panels, and plinths. They are ordered with the kitchen, cut on site, and they decide whether the finished installation looks like a custom fit or a series of boxes pushed against a wall.

None of these items is structural. All three are about appearance and finish. Get them wrong and the eye goes straight to the wavy gap against the wall or the bare chipboard side showing at the end of the run. Get them right and nobody notices them at all, which is exactly the point.

End panels

An end panel covers the exposed visible side of the first or last unit in a run. Without one, the carcass side, which is unfinished chipboard or plain melamine, is on show to the room. A kitchen unit carcass is built to be hidden, so its outer face is rarely finished to the same standard as the doors.

End panels are cut to the full height of the section they sit against. For a base run that means roughly 600mm up to the underside of the worktop. For tall units it means floor to the top of the unit, sometimes floor to ceiling. They fix to the carcass side with adhesive, screws driven from inside the cabinet, or both, and they come in the same finish as the doors so the run reads as one continuous piece. Where a run ends by butting into a return wall, the panel is scribed to the wall profile so it sits tight with no gap.

Filler panels

A filler panel is a narrow strip that fills the gap between the last cabinet in a run and the wall, or between two cabinet runs that do not quite meet. Most kitchen manufacturers supply fillers in set widths: 50mm, 100mm, and 150mm are the common sizes. The fitter cuts the strip down to the exact gap and fixes it between the cabinet frame and the wall.

Fillers exist because carcasses come in fixed increments, usually 300mm, 400mm, 500mm, and 600mm. A wall that measures 3,850mm cannot be filled exactly with six 600mm units, which only reach 3,600mm, or with any other combination of standard sizes. The leftover 250mm is closed with units plus a filler. Plan the run on paper before you order, work out the remainder, and add the right filler to the order. This is the single most overlooked line on a kitchen order.

Scribing

Scribing is the process of marking and cutting a panel so it fits tightly against a wall that is not flat. Almost no wall is flat, especially in an older property or a fresh extension where the plaster is hand-finished.

The panel is held in position at its correct installed height. A scribing block, a small square of timber held flat against the wall, is run down the wall with a pencil resting against it, transferring the exact wall profile onto the face of the panel. The panel is then cut to that pencil line, usually with a jigsaw, and eased back with a sanding block until it seats. A well-scribed panel sits flush to the wall with no daylight behind it. A poorly scribed one leaves a wavy gap that shadow-lines under low or raking light and looks worse the better the rest of the kitchen is.

Plinths and kickboards

The plinth, also called the kickboard, is the horizontal board fitted at the base of the units. It hides the adjustable leg space between the underside of the cabinet and the floor. Standard plinth height is 150 to 175mm, which matches the range the cabinet legs adjust through. Plinths clip on to the cabinet legs or fix with adhesive, and they pull off again for cleaning or for access under the units.

On an uneven floor the plinth is scribed along its bottom edge to follow the floor line, the same technique as scribing an end panel against a wall. Plinths are supplied in the door finish, and on some ranges they can be replaced with integrated push-to-open plinth drawers that reclaim the dead space at floor level for shallow storage.

Cornice and pelmet are separate items

End panels, fillers, and plinths finish the sides and base of the kitchen. The trims at the top are different items and are not covered here. Cornice is the moulding fitted along the top of tall and wall units. Pelmet is the strip fitted under the wall units, often hiding under-cabinet lighting. Both are ordered separately and are dealt with on their own page (content/knowledge/materials/kitchen-units/cornice-and-pelmet.mdx).

Sourcing and finish matching

Filler panels, end panels, and plinths are almost always ordered from the same supplier as the cabinets, in the matching finish. The finish match is the whole reason they exist, so buying them from a different source rarely works: vinyl wraps and paint colours vary just enough between manufacturers to be visible side by side.

For painted kitchens, where the doors are sprayed a custom colour on site, the panels and plinths can be ordered as unfinished MDF and painted in the same batch as the doors so the colour matches exactly. Mass-market suppliers such as IKEA SEKTION, Wren Kitchens, and Magnet list panels and plinths as catalogue items alongside the cabinets. Bespoke manufacturers include them as part of the full specification and cut them to your room on site.

Common mistakes

The most expensive mistake is ordering the kitchen without working out the fillers, then finding on delivery day that the run is 47mm short of the wall and nothing in the box closes the gap. After that, the usual list: not scribing end panels, so a visible wavy gap opens against the wall; fitting the plinth before the floor is level, then having to lift and recut it; over-trimming an end panel until it no longer covers the full carcass side; and specifying a gloss end panel against a matte door run, so the side catches the light differently from everything next to it.

Where you'll need this

• Sourcing units and worktops
• Kitchen installation