What the cable actually buys you
Streaming does not need enormous speed — the speed explainer puts a 4K stream at roughly 15 to 25 Mbps. What it needs is consistent speed. That is exactly what a cable provides and what Wi-Fi sometimes cannot.
An Ethernet cable is a private, dedicated path between your router and one device. Nothing else in the house shares it, no wall weakens it, and no neighbor's network interferes with it. A wired TV gets essentially the same speed at 8 p.m. on a rainy Sunday as at 6 a.m. on a Tuesday.
Wi-Fi, by contrast, is a shared conversation in the air. Every phone, laptop, speaker and tablet on your network takes turns on the same channel. The signal crosses walls and floors, each one taxing it. And because it is radio, it competes with every other network in earshot. Any of these can produce the few seconds of sag that empties a video buffer.
A two-minute diagnosis
Before running any cable, find out whether the wire would actually help:
- Stand next to the TV and run a speed test on your phone over Wi-Fi.
- If the phone, right beside the TV, gets poor or jumpy results, the Wi-Fi in that room is the bottleneck. A cable will fix it.
- If the phone gets strong, steady results but the TV still buffers, look at which band the TV is using (see the Wi-Fi bands explainer) or at the streaming service itself — a cable may change little.
A second quick check: if the TV buffers mostly in the evening while mornings are smooth, congestion is involved. A cable takes your TV out of that fight entirely.
When Ethernet is clearly worth it
- The main TV, far from the router. The single most common case. One cable run replaces years of negotiation with physics.
- A game console. Games punish delay (latency), not just slow speeds, and a cable lowers both.
- A home office sharing the router with a streaming household. Wiring the TV frees Wi-Fi capacity for the calls.
When Wi-Fi is honestly fine
Plenty of setups never need a cable. If the router is in the same room as the TV, or one room away, a 5 GHz or 6 GHz connection is usually more than steady enough — especially for HD rather than 4K. Renters who cannot drill, and TVs that move between rooms, are also reasonable cases for staying wireless and improving it instead: better router position, the right band, or a mesh unit.
Which cable to buy
If you do run a cable, the category printed on it is simpler than the packaging suggests. Cat5e handles gigabit speeds, which is far beyond any stream. Cat6 adds headroom and sturdier construction for a little more money. Anything beyond that is wasted in a living room. Length is the other choice: buy close to the run you need, since coiled excess cable behind a cabinet is the part you will trip over later.
If you cannot run a cable neatly
Three middle options exist, in rough order of reliability: a mesh Wi-Fi unit near the TV (see the router position explainer for placement), powerline adapters that carry the network over your home's electrical wiring (results vary with the age of the wiring), or a flat Ethernet cable run along a baseboard — less invisible than in-wall, but far easier than it looks.
This article is general guidance compiled from networking standards and router manufacturers' documentation. Your router maker's site shows which of its ports and settings apply to your model.