About Heat Pump Tariffs
UK Electricity Tariff Comparison Built by a Heat Pump Owner
Hi, I'm Ashley
I'm a UK heat pump owner. I built Heat Pump Tariffs in 2025 after switching to Octopus Cosy in July of that year and realising that no mainstream comparison site could tell me whether I'd actually picked the right tariff.
The reason: heat pump and EV households spend a lot more electricity than the "typical home" those sites model, and time-of-use tariffs like Cosy, Agile, and Economy 7 depend entirely on when you use it. Without your real half-hourly meter data, comparisons are guesswork.
So I built this. It's free, ad-free, and uses your actual smart meter data to model every UK tariff I can get my hands on. If you've ever wondered whether you'd be better off on a different tariff — this answers that, properly.
What This Site Does
Heat Pump Tariffs takes your real half-hourly smart meter readings and applies them to every UK electricity tariff we track — Standard, Economy 7, Time of Use, and dynamic tariffs like Octopus Agile and Tracker. The result is a ranked comparison showing what you would have paid on each, based on your actual usage pattern rather than a generic national average.
We currently track tariffs from Octopus Energy, EDF, E.ON Next, ScottishPower, British Gas, Good Energy and others — across all 14 UK DNO regions. Rates are refreshed daily from supplier APIs and public data sources.
How It Works
- Connect your smart meter — link the free Bright app (Hildebrand / Glowmarkt platform) so we can pull your half-hourly data automatically, or upload a CSV export.
- We run the comparison — your real usage is applied to every tariff's rate structure for your DNO region, accounting for unit rates, standing charges, and rate bands by time of day.
- See the results — a ranked breakdown by tariff, with monthly analysis and a clear winner for your actual consumption pattern.
Why This Is More Accurate Than Other Comparison Sites
Mainstream comparison sites estimate your bill from a national average usage profile. That's fine for a basic single-rate tariff, but it breaks completely on time-of-use tariffs like Cosy and on dynamic tariffs like Agile, where timing is the entire story. Comparing them by total kWh is like comparing two journeys by total mileage — it misses the point.
We do it differently. Every half-hour slot from your meter is priced against every tariff's rate at that exact slot, then summed. Full technical detail is on the methodology page.
Where the Data Comes From
Tariff rates and standing charges are pulled from supplier APIs (Octopus / Kraken endpoints, EDF, ScottishPower, and others) and refreshed daily by an automated cron job. We do not pay suppliers to be included, and they do not pay us to influence rankings. Full source list and refresh cadence on the data sources page.
How This Is Funded
The site is free to use. If you click through to a supplier from one of our switch links and complete a switch, we may receive a referral fee. This does not influence the comparison results — rankings are derived purely from your usage data and the published rates, in the same way for every supplier whether they pay referrals or not.
Comparison results are estimates based on the rates and meter data available at the time. Future rate changes, exit fees, and any non-standard household circumstances are not modelled. Always verify rates directly with the supplier before switching. Nothing on this site constitutes financial advice.
Your Privacy
Your meter reading data is used only to run comparisons on your behalf. It is never sold or shared with third parties for marketing. Smart meter access via Bright is read-only — we cannot and do not send anything back to your meter. You can delete your account and all associated data at any time from your account settings. Full details in our Privacy Policy.
Get in Touch
Spotted a bug, missing tariff, or have a feature suggestion? I'd like to hear from you.