Hide HDMI & Ethernet in TV Credenza (Back Panel Slot)

To route HDMI and Ethernet through a TV credenza, plan a smooth, protected slot that fits the actual plugs and preserves cable bends, service access, and equipment airflow. Keep communications cables properly separated from power conductors under the locally adopted electrical code. A slot is not a substitute for compliant wiring, and it must not leave cables pinched or exposed to sharp edges.

A neat credenza can still hide a problem: cables may be crushed against the wall, equipment vents may be blocked, or low-voltage leads may be routed too close to power wiring. These issues are easy to miss once the cabinet is pushed into place.

I approach the back-panel opening as a cable route, not just a hole. First check what must pass through it, where it needs to go, and how you will reach the connections later. Then size and protect the opening, route the cables, and test the setup with the credenza in its final position.

Plan the Cable Route and Identify the Applicable Code

A route plan shows where each cable starts and ends, what must pass through the panel, and what could interfere with the path. Before cutting, identify the cabinet’s construction, equipment locations, existing openings, and any power wiring or receptacles. Confirm the locally adopted code and the instructions for your equipment and cables.

Start by laying out the actual HDMI and Ethernet plugs beside the proposed slot. A plug may be much wider than its cable, so measuring only the cable diameter can lead to an opening that is too small. Also check whether the cable can turn behind the panel without a sharp bend.

Measure the back panel’s thickness and note its joints, supports, fasteners, and existing vents. A cut near a joint or attachment point may weaken the panel. There is no generic load rating for a cut credenza back; do not assume that a particular screw size or panel thickness proves it can support a load.

I often find that a quick mock-up prevents rework. Hold the connectors at the proposed opening and trace their path to the devices. Mark the cable route, vent locations, and nearby power conductors before you make a cut.

Check Bend Radius, Power Separation, and Equipment Clearances

Bend radius is the smallest curve a cable can make without risking damage or impaired performance. Power separation is the space or barrier required between certain communications and power conductors. Check both, along with equipment ventilation, before choosing the slot location and route.

For installed balanced twisted-pair cable, a commonly specified minimum bend radius is four times the cable’s outside diameter. Check the cable maker’s instructions, because its limit governs the product. For example, a cable with a 6 mm outside diameter would have a 24 mm bend radius at four times its diameter. Do not apply that figure to HDMI; use the HDMI cable maker’s limit.

NEC 800.133(A)(2) generally calls for 2 inches (50.8 mm) of separation between communications wires and cables and electric-light or power conductors, unless a stated exception applies. Exceptions may involve an effective permanent barrier or a qualifying raceway. Check the adopted edition and the exact conditions. Do not treat a credenza slot as an automatic exception, and do not bundle HDMI or Ethernet tightly against mains wiring without verifying the applicable rule.

There is no universal NEC clearance or airflow value for a credenza. Follow each device maker’s stated clearances and keep its vents open. A slot may help cables pass through, but it does not prove that equipment will stay cool. Check the cabinet with the back near the wall and the devices in their normal positions; the wall or stored items may block the airflow path.

Cut, Protect, and Route the Credenza Back-Panel Slot

The slot should fit the real connectors and cable path, with enough room to install a smooth edge protector. A practical starting size for a small HDMI and Ethernet bundle is 1½ by ½ inches (38 by 13 mm), but this is a design target, not a code minimum. Adjust it to the plugs, cable count, and required bend path.

Before cutting, remove the equipment and check both sides of the panel for wires, fasteners, and supports. Mark the opening away from joints and hardware. Support the panel as you cut, and use rounded corners where practical to reduce stress points. If the back panel is structural or its construction is unclear, do not cut until you have confirmed that the opening will not compromise it.

After the cut, smooth the edges and fit a snug grommet or suitable edge trim. No sharp edge should touch a cable jacket. Keep the opening clear of any required divider or barrier; if the applicable code requires separate routing or a listed divider, follow that requirement rather than sharing an opening by default.

Feed the cables through without pulling hard on the plugs. Secure them so they cannot fall against hot equipment or be crushed when the cabinet moves, but do not clamp them tightly enough to deform the jacket. Leave enough slack to disconnect a device and slide it forward for service.

Situation	Practical check	Safer approach
One HDMI and one Ethernet cable	Test the actual plugs and turning path	Use the 1½ × ½ in. slot only if the bundle fits without forcing
Larger plugs or several cables	Measure the widest connector and cable bundle	Resize the opening while preserving panel strength
Power wiring near the route	Identify cable types and applicable separation rule	Maintain required separation or use an allowed barrier or raceway
Cabinet close to a wall	Check vents and the final airflow path	Keep maker-required clearances; do not count the slot as ventilation

Verify Cable Condition, Service Access, and Ventilation

A finished route is one that stays safe and usable after the cabinet is moved into place. Inspect the cable jackets, check that plugs are not bearing against the slot, and confirm that equipment vents remain clear. Then test the signal and network connection before putting everything back.

Use this sequence after routing:

• Look along each cable for flattening, sharp bends, cuts, or strain at a connector.
• Confirm that the slot trim stays in place and no raw edge contacts a cable.
• Check that the cables remain separated from power conductors as required for the installation.
• Confirm you can unplug and reconnect devices without pulling the credenza away or yanking a cable.
• Place the cabinet in its final position and recheck the cable path, vents, and equipment clearances.
• Test HDMI video and Ethernet connectivity with the devices in their usual positions.

A cable can work during a quick test and still be poorly routed. For example, moving the credenza may pinch it against the wall, or a plug may press against the panel when the cabinet is pushed back. Check the route again after positioning the cabinet.

Do not use this slot to conceal an extension cord or to replace compliant fixed wiring. If the plan involves adding a receptacle, altering fixed wiring, or routing cables through a wall, check local rules and use a qualified electrician where required.

Installation Scenarios: Choose the Route That Fits

These examples are planning scenarios, not claims about a particular home. They show how the same slot idea changes with the cabinet, cable bundle, and nearby equipment. The right opening is the one that fits the real route while preserving panel strength, separation, and airflow.

Single TV connection: One HDMI cable and one Ethernet cable pass through the back panel to a device inside the credenza. Mock up both plugs first. If the starting-size slot accepts them without force and leaves a safe bend path, add edge trim and retain enough slack for service.

Several devices and a narrow cabinet: Multiple HDMI leads, network cables, and power connections crowd the rear space. Do not simply enlarge one opening and push everything through together. Map each route, check which cables are power and which are communications, and apply the relevant separation rules. A larger opening also removes more panel material, so verify the cabinet construction before cutting.

Credenza close to the wall: The slot appears open while the cabinet is pulled forward, but the wall blocks part of it when the cabinet is returned to position. Check the actual installed position. Keep equipment vents clear and ensure the wall does not pinch cables or press connectors against the panel.

Frequently Asked Questions

These answers cover common decisions about slot size, code, cable bends, and safe finishing. The exact requirements depend on the adopted code, the cable and equipment instructions, and the credenza’s construction. When a rule or panel limit is uncertain, verify it before cutting or routing.

How large should a credenza cable slot be?
A 1½ by ½ inch (38 by 13 mm) slot is a practical starting point for a small HDMI and Ethernet bundle. Measure the plugs and route first; this is not a code minimum.

Does an HDMI cable fit through a small slot?
The cable may fit while its connector does not. Measure the widest plug and test the turning path before cutting.

Can HDMI and Ethernet share one slot?
They may pass through the same protected opening if the arrangement meets applicable code requirements and does not force, pinch, or damage either cable. Check power separation where relevant.

How far should Ethernet bend behind the panel?
Follow the cable maker’s bend-radius limit. A commonly specified minimum for installed twisted-pair cable is four times its outside diameter; do not use that value for HDMI without manufacturer guidance.

Does the slot count as a barrier between low-voltage and power wiring?
No. A furniture slot is not automatically an approved barrier or an exception to a separation rule. Verify the adopted code and the installation conditions.

Can I hide an extension cord behind the credenza?
Do not use the back-panel slot to conceal an extension cord or substitute for compliant fixed wiring. Follow the cord and equipment instructions, and consult a qualified electrician about fixed wiring changes.

Will a slot keep my receiver or game console cool?
Not by itself. Keep vents open and follow the equipment maker’s clearance instructions. Check airflow with the cabinet in its final position.

How do I protect cables from the cut edge?
Deburr the opening and install a smooth, fitted grommet or edge trim. Inspect it to ensure no sharp edge can touch a cable jacket.

Can I cut any credenza back panel?
No. Check the panel material, supports, joints, and fasteners first. There is no generic load rating for a panel after cutting.

How much service slack should I leave?
Leave enough cable to disconnect and move the device forward for access, while keeping the slack from being pinched or blocking vents. The needed amount depends on the cabinet layout and connector position.

(This article was written by one of our staff writers, Michael Holloway. Visit our Meet the Team page.)