SMETS1 vs SMETS2: What’s The Difference?

The generation of smart meter in your home determines whether it keeps working properly when you switch energy suppliers. For households with a first-generation SMETS1 meter, changing supplier can strip away its smart functions entirely, leaving you submitting manual readings or stuck with estimated bills. 

This isn't a rare problem: nearly 40 million smart and advanced meters have been installed across Great Britain, according to government figures in the Q2 2025 Smart Meters Statistics Report, and a significant share of those are still first-generation devices. This guide explains how to identify which meter you have, what happens if you switch supplier, and whether you need to do anything about it.

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Key Takeaways

• SMETS1 smart meters can revert to manual operation after a supplier switch, stopping automatic readings and causing estimated bills until readings are submitted manually or the meter is enrolled onto the national DCC network.
• SMETS2 meters connect to the Data Communications Company (DCC) national network, maintaining smart functionality regardless of which energy supplier the household uses.
• Most SMETS1 meters are being progressively enrolled onto the DCC network through a government-backed migration programme, but enrolment is not automatic for all meters; households should check their status through their supplier account rather than assuming migration has occurred.
• For households with solar panels, battery storage, or EV chargers, SMETS2 connectivity supports reliable two-way data flow, accurate export tracking under the Smart Export Guarantee (SEG), and access to advanced time-of-use tariffs that optimise charging costs.

What SMETS1 and SMETS2 Actually Mean

SMETS1 and SMETS2 refer to the two generations of UK smart meter, defined under the Smart Metering Equipment Technical Specifications (SMETS) programme. 

The distinction that matters most in practice is how each generation communicates: SMETS1 meters connect to individual supplier networks, while SMETS2 meters connect to the shared national network operated by the Data Communications Company (DCC), making them compatible with any supplier from the outset.

What Is a SMETS1 Smart Meter?

A SMETS1 smart meter is a first-generation device installed from approximately 2013 onwards, linked to the communication infrastructure of the energy supplier who fitted it. Because the meter’s smart functions depend on that specific supplier’s network, switching to a new supplier can sever the connection. 

When this happens, the meter enters what is sometimes called “dumb meter mode”: it continues recording your gas and electricity consumption accurately, but stops sending readings automatically. Your new supplier cannot access your real-time energy usage data, so bills are estimated until you provide readings manually.

What Is a SMETS2 Smart Meter?

A SMETS2 smart meter connects directly to the DCC’s national wide area network (WAN), which sits independently of any individual energy supplier. This interoperability means the meter retains its smart functions when you switch supplier, because the new supplier simply connects to the same shared network. All new smart meter installations since around 2019 are SMETS2, and Ofgem requires suppliers to offer smart meter installation to domestic customers as part of the national rollout.

How To Tell Which Meter You Have

The most reliable way to confirm your meter generation is to log into your energy supplier’s online account, where your meter type and DCC enrolment status are typically displayed. If that is not immediately visible, three practical checks will give you a strong indication.

• Quickest check: Log into your supplier’s online account and look for “meter type” or “smart meter details.” If your meter shows as DCC-enrolled, it is operating as a SMETS2-equivalent regardless of its physical generation.
• Installation date is the simplest starting point. Meters installed before 2019 are likely to be SMETS1; those installed from 2019 onwards are almost certainly SMETS2, though meters fitted in the transition period of 2018–early 2019 may be either generation.
• Meter serial number can sometimes indicate the manufacturer, which in turn suggests the generation. However, no single public lookup tool covers all models definitively, so treat this as a prompt to investigate further rather than a definitive answer.
• Your In-Home Display (IHD) is not a reliable indicator on its own. A working IHD does not confirm SMETS2 status. Read on for why.

Checking Via Your Supplier Account

Logging into your supplier’s online account is the most accessible and definitive route. Look for a section labelled “meter details,” “smart meter,” or “my meter.” Many suppliers now display whether your SMETS1 meter has been enrolled onto the DCC network. 

If the information is not visible online, calling the supplier’s smart metering team and asking specifically about your meter’s DCC enrolment status will give you a direct answer. The Smart DCC’s SMETS1 enrolment programme page also provides background on which meter types are covered by the migration process.

What Your In-Home Display Can and Cannot Tell You

An In-Home Display shows your real-time energy consumption by communicating locally with your meter via a short-range signal, a connection that works independently of whether the meter is sending data to your supplier over the national network. A SMETS1 meter in dumb mode can still display current usage on the IHD, even though it has stopped transmitting readings remotely. That means a working IHD:

• Confirms: the local connection between your meter and display is intact
• Does not confirm: that your meter is enrolled on the DCC network
• Does not confirm: that it’s functioning as a full smart meter for billing purposes

What Happens to Your SMETS1 Meter When You Switch Supplier

When a household with an un-enrolled SMETS1 smart meter switches to a new energy supplier, the meter typically loses its connection to the original supplier’s network and cannot automatically reconnect to the new one. What happens next follows a consistent pattern:

• The meter continues to measure your gas and electricity consumption accurately
• It stops sending readings automatically to your new supplier
• Your new supplier receives no automated consumption data, so bills are either estimated or you must submit readings manually until the situation is resolved

This is not a fault with the meter itself. It reflects how SMETS1 meters were designed: each one was tied to the communication infrastructure of the installing supplier rather than to a shared national system. The practical consequence is that a meter which worked perfectly before the switch may appear to have stopped functioning, even though it’s still recording accurately behind the scenes.

It’s important not to overstate this as a universal problem. SMETS1 meters that have already been enrolled onto the DCC network through the national migration programme behave more like SMETS2 meters, and for those households, switching supplier no longer causes a loss of smart functionality. Whether your specific meter has been enrolled is the key question, and checking via your supplier account gives you a direct answer.

The SMETS1 National Migration: What It Means For You

The DCC has been working with energy suppliers to enrol eligible SMETS1 meters onto the national network, a process known as enrolment and adoption. Once enrolled, a SMETS1 meter maintains smart functionality across supplier switches and supports automatic remote meter reading, resolving the core problem described above. Enrolment happens via a remote firmware update, so no engineer visit is required for this step alone.

What Enrolment Means in Practice

In practice, enrolment isn’t instant, and it hasn’t reached every meter yet. The programme is still rolling out, so your specific meter might not have been migrated even if others nearby have. The only reliable way to find out where you stand is to check your supplier account or call their smart metering team and ask directly.

There’s one thing worth knowing before you switch supplier or check your status: while your meter is being enrolled, your In-Home Display can go a bit unreliable for a few days, showing figures that don’t quite add up. That’s a normal part of the meter reconnecting to the new network, not a sign anything’s gone wrong. If this happens shortly after a known migration window, giving it a few days before contacting your supplier is a reasonable first step.

What To Do If Your Meter Is Not Eligible for Enrolment

Some older SMETS1 models, or those with specific connectivity limitations, aren’t compatible with remote enrolment. Where that’s the case:

• Restoring full smart meter functionality requires a physical SMETS2 replacement rather than a firmware update
• The replacement is typically arranged through your energy supplier
• It’s generally provided at no cost to the consumer, though policies vary between suppliers

Checking gov.uk for current guidance on the national smart meter rollout gives the most up-to-date information on what households are entitled to request.

Rented Properties and SMETS1 Meters

In most rented properties, the energy account is held by the tenant, who is the energy supplier’s customer, as outlined in Citizens Advice guidance on energy bills in rented homes. In practice, that means:

• The tenant can typically request a smart meter upgrade or SMETS2 replacement directly from the supplier without requiring landlord approval
• The meter is the supplier’s asset, not a modification to the property, so most standard replacements fall outside the landlord’s decision-making authority

Some landlords may raise concerns where the meter location requires physical alteration or access to communal areas, though in straightforward cases this shouldn’t obstruct a replacement. If a supplier requires landlord consent for a specific installation and the landlord declines:

• The practical route is to raise the matter directly with the supplier
• Suppliers have obligations under the national rollout programme
• A supplier’s smart metering team can advise on escalation options where access is being unreasonably withheld

Why SMETS2 Matters More If You Have Solar, Battery Storage, or an EV Charger

For households with solar panels or those planning to install them, the relationship between smart meter and solar panels is directly affected by meter generation. A SMETS2 meter supports reliable two-way data flow, meaning both what you import from the grid and what you export back to it are tracked accurately and automatically.

SEG Export Tracking and Meter Accuracy

The Smart Export Guarantee (SEG) is the rate your energy supplier pays you for unused electricity you send back to the grid. SEG payments depend on verifiable export data flowing reliably from your meter to your supplier. A SMETS1 meter in dumb mode cannot transmit this data consistently, which can create discrepancies in SEG payments or require manual verification. 

A SMETS2 meter provides the consistent reporting that export tariffs require, making it the more reliable foundation for using smart meter data to optimise solar usage. Solar panels operate independently of the meter and will continue generating regardless of meter generation, but accurate export tracking depends on consistent communication.

Time-of-Use Tariffs and Battery Charging

Advanced time-of-use tariffs, which allow households to charge battery storage or EVs at lower overnight rates and discharge during more expensive periods, require half-hourly energy data to function correctly. A SMETS1 meter in dumb mode cannot supply this data stream, which means the household cannot participate in tariffs that shift charging to reduce bills. 

A SMETS2 meter delivers the consistent half-hourly energy consumption data these tariffs require. For homes using a Skygate® home energy management system to integrate solar, battery, EV, and heat pump into a single platform, SMETS2 connectivity provides the reliable, granular data flow that makes automated optimisation possible.

When a SMETS1 Meter Is Not a Problem

For households with a SMETS1 meter that has already been enrolled onto the DCC network, the practical differences from SMETS2 may be minimal. A successfully enrolled SMETS1 meter:

• Maintains smart functionality across supplier switches
• Supports automatic reading

The primary failure mode is resolved.

The same is largely true if you meet all of the following:

• No plans to switch energy supplier
• No solar panels or battery storage
• No interest in advanced tariffs

In that case, an un-enrolled SMETS1 meter creates limited immediate disruption, the main downside is the inconvenience of submitting manual readings if you do eventually switch. That said, UK energy policy is moving toward time-of-use tariffs, smart charging, and grid flexibility, all of which depend on the kind of reliable metering SMETS2 provides. Addressing your meter status now avoids having to revisit it at a less convenient moment.

How Upvolt Supports Homes Moving Toward Smarter Energy Management

System design for solar, battery storage, and smart energy management goes beyond roof orientation and panel count. It includes understanding how a home’s existing infrastructure, including meter generation, affects what the installation can achieve.

Assessing Metering Compatibility During System Design

During an Upvolt assessment, the household’s metering setup forms part of the evaluation alongside tariff structure and energy usage patterns. A home with an un-enrolled SMETS1 meter may need to address that before advanced tariff-linked battery charging or accurate SEG export tracking can function correctly. Identifying this dependency early means households have a clear picture of what the installation will deliver before any investment decision is made.

Integrating Skygate® With a SMETS2-Ready Home

Upvolt’s Skygate® home energy management system draws on smart meter data alongside solar generation figures, battery state of charge, and EV charging status to optimise energy flow across the whole household. What we find in practice is that SMETS2 connectivity gives the system the consistent, half-hourly data stream it needs to make meaningful automated decisions, particularly when time-of-use tariffs are active. A SMETS1 meter that has not been enrolled introduces gaps in that data flow, which reduces the system’s ability to optimise effectively.

What Homeowners Get From an Upvolt Assessment

Upvolt’s assessment gives you clarity on what a solar or battery installation will actually achieve for your specific home, covering what the system would generate, what your meter situation means for tariff access and export tracking, and what steps, if any, you’d need to take before installation. There is no obligation to proceed.

Let’s Recap

SMETS1 and SMETS2 meters differ in one consequential way: how they communicate. A SMETS1 meter connects to the individual supplier who installed it, so switching supplier can sever that connection and push it into dumb mode, where it keeps measuring accurately but stops transmitting readings automatically. A SMETS2 meter connects to the DCC’s shared national network instead, so it keeps working regardless of which supplier you use. 

Many SMETS1 meters are being progressively enrolled onto that network through the national migration programme, restoring smart functionality without a hardware swap, but enrolment isn’t instant or universal, so it’s worth checking your status through your supplier rather than assuming it’s already happened.

For homes with solar panels, battery storage, or an EV charger, meter generation directly affects what the system can deliver: SMETS2 supports accurate SEG export tracking, the half-hourly data advanced tariffs need, and the consistent data flow home energy management systems depend on, while a SMETS1 meter in dumb mode limits all three. SMETS2 is already the standard for new installations, and as UK energy policy leans further into time-of-use tariffs, smart charging, and grid flexibility, sorting out your meter status now means you’re ready for what’s coming rather than catching up later.

About Upvolt

Upvolt is a renewable energy installer operating across southern England, helping homeowners understand how their home’s existing infrastructure, including their smart meter generation, affects the value they can get from solar, battery storage, and smart energy installations. Metering compatibility is not a technical afterthought. It shapes tariff access, export tracking accuracy, and how effectively a home energy management system can optimise across multiple devices.

Upvolt installs solar panels, battery storage, EV chargers, and heat pumps, and integrates these through the Skygate® home energy management system. These products are designed to work together rather than in isolation, and system design reflects that. A battery installation that cannot access time-of-use tariff data because of an un-enrolled SMETS1 meter will underperform relative to one that can. Getting that dependency identified early is part of how Upvolt approaches system design.

A SMETS1 meter that’s never been enrolled can quietly hold back a solar or battery system from doing what it’s actually capable of, and most homeowners find that out after installation rather than before. Upvolt checks for that upfront. Get a free, no-obligation quote, and know exactly what you’re working with before any equipment goes on your roof.

FAQ

Will My SMETS1 Smart Meter Stop Working If I Switch Energy Supplier?

A SMETS1 meter in dumb mode does not stop measuring your energy, but it will stop sending readings automatically to your new supplier. Bills are typically estimated until you submit readings manually or until the meter is enrolled onto the DCC network. Whether this affects your specific meter depends on its enrolment status, which your supplier account can confirm.

How Do I Find Out Whether I Have a SMETS1 or SMETS2 Smart Meter?

The most reliable method is your energy supplier’s online account, which typically shows meter type and DCC enrolment status. As a rough guide, meters installed before 2019 are likely SMETS1; those installed from 2019 onwards are almost certainly SMETS2. A functioning In-Home Display is not a reliable indicator, since a SMETS1 meter can show local real-time energy usage even when it has lost its network connection to the supplier.

Can I Get My SMETS1 Meter Upgraded to SMETS2 for Free?

In most cases, yes. Upgrading from SMETS1 to SMETS2 is generally arranged through your energy supplier at no cost to the consumer, though policies vary. Not all SMETS1 meters are eligible for remote enrolment; some older models require a physical replacement rather than a firmware update. Checking gov.uk for current guidance on the smart meter rollout gives the most accurate picture of what you are entitled to request.

Does It Matter Which Meter I Have If I Am Planning to Install Solar Panels?

Meter generation affects how accurately your solar export is tracked and whether you can access advanced tariffs that improve battery and EV charging returns. A SMETS2 meter supports reliable two-way data flow for SEG export reporting and half-hourly consumption data for smart tariffs. A SMETS1 meter in dumb mode cannot provide this, which can affect SEG payment accuracy and limit tariff access. Addressing meter status before or alongside a solar installation avoids these complications.

Who Is Responsible for Requesting a Smart Meter Upgrade in a Rented Property?

In most rented properties, the tenant holds the energy account and can request a smart meter installation or SMETS2 upgrade directly from the supplier without landlord approval. The meter is the supplier’s asset, not a modification to the property. If a landlord raises objections to access arrangements for a specific installation, the supplier’s smart metering team can advise on the appropriate next steps.

Alex Lomax

CEO & Co-Founder

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