Cheapest electricity tariff for an air source heat pump (UK guide)
There isn’t one single “cheapest” tariff for heat pumps in the UK. The best option depends on your meter type (single-rate vs Economy 7 vs smart/time-of-use), how much you can run the heat pump off-peak, and your region. This guide shows how to choose a tariff that matches how heat pumps use electricity.
- Find tariffs that suit heat pumps: single-rate, Economy 7 and smart off-peak options
- See estimated examples with numbers (and what assumptions we used)
- Understand pitfalls: standing charges, export/EV bundles, exit fees, eligibility and meter requirements
Estimates only. Tariffs, rates and eligibility vary by region, payment method and meter type. We’ll ask a few details to show options available at your postcode.
Fast answer: what’s usually cheapest for a heat pump?
For most UK homes with an air source heat pump, the “cheapest electricity tariff” is the one that best matches when your heat pump runs and what meter you have:
Most common fit
Single-rate fixed or variable tariff often wins if you can’t reliably shift usage overnight (typical for families and homes without a hot water cylinder schedule).
Can be cheaper
Economy 7 can work if you can push a meaningful share of heat pump/hot water to night-rate (and your daytime rate isn’t too high).
Potentially best (with caveats)
Smart time-of-use/off-peak tariffs may reduce costs if you can schedule hot water, pre-heat, or have a buffer tank—but the peak rate can be expensive.
Key takeaway: the cheapest tariff is rarely about the headline unit rate alone. For heat pumps, standing charge + day rate + off-peak rate + how many kWh you can move off-peak matter more than brand names.
- You’re most likely to benefit from off-peak if…
- You have a smart meter or Economy 7 meter, a hot water cylinder you can schedule, and you can comfortably run more overnight (e.g., hot water and pre-heat).
- You’re often better on a standard single-rate tariff if…
- Your heat pump runs steadily through the day (common in colder spells), you’re home during the day, or you can’t shift much load without comfort issues.
Compare electricity tariffs suited to heat pumps
Tell us a few details and we’ll show available tariffs for your postcode, including options that may suit heat pump running patterns (single-rate, Economy 7 and smart/off-peak where available).
Tip: If you know your meter type (single-rate, Economy 7, smart meter) and whether you have a hot water cylinder, include it in your notes when we contact you—this can change which tariff is genuinely cheapest.
How to choose (quick process)
- Confirm your meter: single-rate, Economy 7, or smart meter (time-of-use eligibility varies by supplier).
- Estimate heat pump share: what % of your electricity is heat pump + hot water (often higher in winter).
- Check load shifting: can you schedule hot water/pre-heat overnight without comfort issues?
- Compare total cost, not just unit rate: standing charge + day + night/peak rates + any discounts/fees.
- Check contract terms: exit fees, price change terms (variable), and eligibility rules (e.g., smart meter requirement).
Get your heat pump electricity quote
We use your postcode to show tariffs available in your region. No guarantees—prices depend on supplier availability and your meter type.
Tariff types for air source heat pumps: what to compare
Heat pumps are efficient, but they still use a lot of electricity across the year. The right tariff depends on your ability to use cheaper hours without making your home uncomfortable.
| Tariff type | When it can be cheapest | Main watch-outs | Who it suits |
|---|---|---|---|
| Single-rate (standard) | If most usage is daytime/evening, or you can’t shift load reliably | May miss out on low overnight prices; standing charge still matters | Families, home working, steady comfort settings |
| Economy 7 | If you can push a meaningful share to night rate (often via hot water scheduling) | Day rate can be higher; night hours vary by region/meter; needs the right meter | Homes with a cylinder, good controls, and willingness to schedule |
| Smart time-of-use | If you can use cheap windows for hot water and/or pre-heating | High peak rates; eligibility rules; prices can change; requires smart meter | Tech-comfortable users, flexible schedules, homes with thermal mass |
| EV bundle tariffs | Sometimes, if you also charge an EV overnight and can align other usage | May require EV ownership; cheap hours may be short; peak rate can be high | Heat pump + EV households with smart meter |
Decision checklist (quick)
- Do you have a smart meter or Economy 7 meter already?
- Can you schedule hot water (cylinder) into off-peak hours?
- Are you happy with pre-heating (slightly warmer earlier) to reduce peak-time running?
- What’s your standing charge and does it wipe out rate savings?
- Is there an exit fee or a long fixed term?
Who off-peak tariffs suit (and who they don’t)
Good fit
- Smart controls / willingness to tweak schedules
- Hot water cylinder, buffer tank or good thermal mass
- Comfortable avoiding peak windows where possible
Not ideal
- Most heating demand is daytime and you can’t shift it
- Limited controls or rental restrictions on meter changes
- You’d risk comfort (cold spells) to chase off-peak
Two realistic examples (with numbers)
These examples show how the “cheapest” tariff can change depending on how much electricity you can use off-peak. They are illustrative only (rates vary by supplier and region, and standing charges can change the outcome).
Assumptions for both scenarios (for comparability): electricity use 6,000 kWh/year (including heat pump), standing charge £0.60/day, and example unit rates: single-rate 26p/kWh; Economy 7 day 30p/kWh + night 16p/kWh; time-of-use peak 35p/kWh + off-peak 12p/kWh. Your real rates may be higher/lower.
Scenario A: steady daytime heating (limited shifting)
A couple working from home, comfort kept steady. Off-peak share: 20% (hot water mostly daytime).
| Tariff (example) | Estimated unit cost | Estimated annual total |
|---|---|---|
| Single-rate (26p) | 6,000 × 26p | £1,929 (usage £1,560 + standing £219) |
| Economy 7 (20% night) | 4,800 × 30p + 1,200 × 16p | £2,022 (usage £1,803 + standing £219) |
| Time-of-use (20% off-peak) | 4,800 × 35p + 1,200 × 12p | £2,043 (usage £1,824 + standing £219) |
What this shows: if you can’t shift much usage, a good single-rate tariff can be cheaper than off-peak options with higher daytime/peak rates.
Scenario B: scheduled hot water + some pre-heat
A family with a cylinder. Hot water set to heat overnight; mild pre-heat before peak. Off-peak share: 45%.
| Tariff (example) | Estimated unit cost | Estimated annual total |
|---|---|---|
| Single-rate (26p) | 6,000 × 26p | £1,929 (usage £1,560 + standing £219) |
| Economy 7 (45% night) | 3,300 × 30p + 2,700 × 16p | £1,642 (usage £1,423 + standing £219) |
| Time-of-use (45% off-peak) | 3,300 × 35p + 2,700 × 12p | £1,696 (usage £1,477 + standing £219) |
What this shows: once you can move a larger share off-peak, Economy 7 or time-of-use can beat a standard single-rate tariff—but only if the daytime/peak price isn’t too punishing.
Reality check: heat pump demand is seasonal. A tariff that looks good on an annual average can feel expensive in winter if your peak rate is high and you can’t shift enough. If you’re unsure, start by comparing a competitive single-rate tariff against one off-peak option.
Costs, exclusions and common pitfalls (heat pump-specific)
1) Standing charges can dominate
Even if your unit rate is lower, a higher standing charge can reduce or wipe out savings—especially in smaller flats with lower overall kWh use.
2) Economy 7 hours aren’t universal
Your off-peak window depends on your meter set-up and region. Don’t assume it’s always midnight–7am. Confirm your exact night hours before changing heating schedules.
3) Peak rates on time-of-use can be very high
If your heat pump runs during peak windows in cold weather, costs can rise quickly. Time-of-use works best when you can confidently avoid expensive hours.
4) Smart meter requirements (and delays)
Many off-peak tariffs require a communicating smart meter. If your meter can’t be upgraded quickly (or signal is poor), eligibility may be limited.
5) Exit fees and fixed-term lock-ins
Fixed deals can protect against rises, but check exit fees and end dates. If you’re trialling a time-of-use tariff, flexibility may matter more than a small rate difference.
6) Don’t chase off-peak at the expense of comfort
Heat pumps typically run best steadily. Aggressive on/off scheduling can reduce comfort and may not reduce costs. If in doubt, optimise controls first, then tariff.
If you rent: you can usually choose your electricity supplier, but changing meter type (e.g., adding Economy 7 or smart meter work) may need landlord permission or practical access. Always check your tenancy terms.
FAQs
Is there a dedicated “heat pump tariff” in the UK?
Not usually as a standard category. Most households choose between single-rate, Economy 7, or smart time-of-use/off-peak tariffs. The right choice depends on your ability to shift usage and the rates available at your postcode.
Do I need a smart meter for cheaper heat pump electricity?
You don’t need one for competitive single-rate tariffs, but many off-peak/time-of-use tariffs require a smart meter. If you’re considering time-of-use, confirm smart meter eligibility before switching.
Is Economy 7 good for air source heat pumps?
It can be, but only if you can move enough electricity into the night-rate window (often via hot water scheduling). If your heat pump must run mainly in the day (or your day rate is high), Economy 7 may cost more overall.
What if I have solar panels and a heat pump?
Solar can reduce daytime import, which may make a high day rate less painful—but winter generation is lower, when heat pumps use more. Compare tariffs on annual cost and check export terms if you export to the grid (export rates are separate from import tariffs).
Will switching electricity supplier affect my heat pump warranty or servicing?
Switching supplier typically doesn’t affect your heat pump equipment warranty, as the warranty is linked to the product/installer terms. However, if you change settings to chase off-peak rates, keep them within the manufacturer’s guidance and your installer’s recommendations.
Can I switch if I’m on a prepayment meter?
Often yes, but tariff availability can be more limited and prices may differ. Some suppliers require certain meter types for specific off-peak tariffs. If you’re struggling to afford top-ups, you can get help and guidance via Citizens Advice.
How do I know what meter I have (single-rate vs Economy 7)?
Check your electricity bill for two unit rates (day and night) or “Economy 7”. Some meters show separate readings (e.g., R1/R2). If you’re not sure, we can help interpret it during your comparison.
Is a fixed tariff always better for a heat pump?
Not always. A fixed deal can help with budgeting, but may be less flexible if you want to change again after testing an off-peak tariff. Compare the total estimated cost and check exit fees before committing.
Trust, methodology and sources
Page ownership
- Written by
- EnergyPlus Editorial Team
- Reviewed by
- Energy Specialist
- Last updated
- May 2026
How we assess what’s “cheapest” for a heat pump
We focus on total estimated annual cost, not just the headline unit rate. For heat pumps, the cheapest tariff is driven by:
- Standing charge (paid daily regardless of usage)
- Day/peak unit rate (often where heat pumps run most in winter)
- Night/off-peak rate and how many kWh you can realistically shift
- Eligibility (meter type, smart meter requirement, payment method)
- Contract terms (exit fees, fixed term, price change terms for variable tariffs)
Limitations: We can’t guarantee availability or the exact bill you’ll pay. Network charges vary by region, suppliers update prices, and your heat pump consumption changes with weather, insulation and settings.
Sources (UK)
- Ofgem (UK energy regulator) – guidance on switching and consumer protections
- Citizens Advice: Energy – support with bills, meters and supplier issues
- GOV.UK: Boiler Upgrade Scheme guidance – scheme information (installation support; not tariff pricing)
Ready to find a cheaper electricity deal for your heat pump?
Compare whole-of-market tariffs available in your area and check which ones fit how your heat pump actually runs.
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