Shelly Plug S MTR Gen3

A neat plug with a difficult price

The most appealing part of Plug S Gen3 is its small round body and transparent light ring. At 44 mm across, it is relatively unobtrusive beside a lamp or desk. The ring can show power consumption through changing colors, use a color you choose, or stay off. Being able to reduce its brightness at night makes that decoration easier to live with.

At the official €23.90 EU list price, however, this is no longer an obvious first choice. On September 9, 2026, both black and white listings were out of stock. Shelly's newer Plug M Gen3 was available for €12.90, also with Matter, switching and power monitoring. Those prices include VAT, with shipping extra.

The M is a little larger at 46 × 46 × 85 mm against the S's 44 × 44 × 70 mm, and its rating is higher: 13 A/3000 W against 12 A/2500 W. Paying €11 more for the S makes sense where its smaller enclosure solves a real space problem. For an ordinary lamp outlet, start with the cheaper model.

Useful controls, with a scripting catch

Shelly gives this plug more independence than a simple cloud-controlled switch. Its built-in browser interface handles local control and settings, while stored schedules can run the everyday routine. A physical button remains available to switch the appliance without reaching for a phone. Shelly Cloud is optional for local use.

There is a significant qualification for enthusiasts: the exact S MTR Gen3 documentation supports onboard scripting only when Matter is disabled. You cannot buy it expecting both custom scripts on the plug and a Matter connection at the same time. That restriction does not remove ordinary Matter routines or the plug's schedule controls, but it weakens the pitch for this as an all-purpose automation tool.

Power monitoring is useful for seeing what a connected appliance consumes. Detailed readings and settings are available through Shelly; the light ring gives a quick indication rather than a numerical meter. Buy it for those specific views, without assuming that every Matter app will reproduce the same history.

Keep one you own; be selective about buying more

The 12 A/2500 W resistive-load limit is lower than that of many full-size European sockets. This is an indoor adapter for suitable loads, not a way to make an arbitrary high-power appliance smart. The manual also excludes directly attached plug-in transformers and chargers, so its compact shape does not make it a universal power-strip accessory.

For a working installation, there is little reason to replace the S just because the M is cheaper. It already offers local schedules, adjustable indicators and direct Matter control. For a fresh purchase, its shape needs to earn the price difference. Otherwise, the less expensive M is the more convincing starting point.