SMETS1 vs SMETS2 Smart Meters

SMETS1 is the first generation of UK smart meter, rolled out from around 2011 to 2018. It was designed to end estimated billing by sending automatic readings to your supplier and showing live usage on an in-home display.

Early SMETS1 meters had teething problems. Because each supplier used its own communications system, many meters historically lost their smart functions after a supplier switch, dropping back to manual readings until they could be reconnected.

To fix this, SMETS1 meters have been enrolled onto the national DCC network (the same secure network SMETS2 meters use). The vast majority are now enrolled, which restores supplier-independent smart functionality without a physical replacement. If your older meter has quietly gone "dumb", our smart meter problems guide explains how to get it working again.

SMETS2 is the second-generation smart meter and the UK standard for every new installation. It was built to solve SMETS1's biggest weakness: it works seamlessly across all energy suppliers.

SMETS2 meters connect to the secure national DCC network from day one, so readings keep flowing automatically no matter who supplies your energy. Communications are more reliable, and firmware updates are delivered over the air to keep the meter current.

Crucially, SMETS2 is future-ready infrastructure. It's designed to support smart and time-of-use tariffs, EV charging and solar export tracking — which is why it's the meter to request if you're comparing options on our Supplier Monitor.

Yes. SMETS1 meters still record your usage accurately and remain perfectly legal. The national DCC migration programme has enrolled the vast majority onto the same network SMETS2 meters use, so they send automatic readings and keep smart features when you switch supplier.

A small number of very old units can't be enrolled and may still drop to manual readings. In those cases — or if the meter is faulty — replacement with a SMETS2 may be appropriate, and your supplier will do this free of charge.

If your SMETS1 meter is enrolled and sending readings, there's usually no urgent need to upgrade. Suppliers typically offer a SMETS2 replacement when your existing meter is faulty, can't be enrolled, or when you want access to the newest smart tariffs.

The benefits of upgrading include rock-solid connectivity, over-the-air updates and full support for time-of-use, EV and solar tariffs. But remember: a smart meter doesn't lower your unit rate on its own. Real savings come from acting on the data and choosing the right tariff — check whether that's worth it with Should I Switch Supplier?

On consumer rights: smart meters are free, and you can't be forced to have one. You're entitled to ask your supplier which meter you have and whether a replacement is available.

With a SMETS2 meter (or an enrolled SMETS1), switching is seamless. Your readings keep flowing automatically, your new supplier picks up smart data straight away, and no engineer visit is needed.

With an older, un-enrolled SMETS1 meter, switching could temporarily reduce it to manual readings until it's reconnected — but this now affects only a small minority of meters.

A common misconception is that switching "breaks" your smart meter. It doesn't. Before you switch, note your latest readings, confirm your meter type, then compare tariffs with our switching guide and cheapest supplier pages.