Energy tariffs with free electricity hours: UK comparison guide
Compare UK energy tariffs that offer “free” electricity for set hours (often overnight, or at weekends). Learn how they work, who they suit, what to watch for, and how to compare them fairly by total cost.
- Understand how “free hours” are funded (and why unit rates can be higher outside the free window)
- Check eligibility: meter type, region, and whether smart meter half-hourly readings are required
- See two realistic cost scenarios with assumptions, so you can sanity-check offers
Figures on this page are examples only. Tariff availability and terms vary by supplier, region, meter type and payment method. Always check the tariff facts before switching.
Fast answer: are “free electricity hours” tariffs worth it?
They can be worth it if you can reliably shift a meaningful chunk of your electricity use into the free window (for example EV charging, tumble drying, dishwasher/laundry, or some home battery charging). If you can’t, you may pay more overall because the paid unit rate and/or standing charge can be higher to fund the “free” hours.
Usually suits
- EV owners who can schedule charging
- Homes happy to run appliances at set times
- Smart meter households comfortable with half-hourly data
Usually not ideal for
- Low users who can’t shift much usage
- Households with unpredictable routines
- Those who prefer simple single-rate tariffs
Quick checks
- Do the “free” hours match when you can use power?
- Is there a higher unit rate outside the window?
- Any exit fees, minimum terms, or smart-meter requirements?
Important: “Free” typically means 0p/kWh unit rate during a defined time window. You’ll still pay the standing charge, and you may pay higher rates outside the window. Some tariffs are electricity-only; your gas supply (if any) is separate.
How energy tariffs with free hours work in the UK
These tariffs offer a set time window where the electricity unit rate is reduced—sometimes to 0p/kWh. In return, the supplier may charge a higher unit rate outside the window, a different standing charge, or set eligibility rules.
Common types you’ll see
- Fixed “free hours” each day
- Often overnight (useful for EV charging). Outside those hours, you pay a standard (sometimes higher) unit rate.
- Weekend “free periods”
- Certain hours on Saturdays/Sundays may be discounted. Good if you do laundry/drying on weekends.
- Smart, half-hourly pricing (dynamic)
- Prices can vary by half hour. Some suppliers may promote “free” sessions or special events. Your bill depends heavily on when you use electricity.
Eligibility and UK-specific constraints
- Meter type: many free-hour tariffs require a smart meter with half-hourly readings enabled.
- Region: tariffs and rates vary by electricity distribution region (your postcode matters).
- Payment method: Direct Debit rates can differ from prepayment; some tariffs are not available for prepayment meters.
- Heat pumps & storage heaters: check if a dedicated multi-rate option (e.g., legacy Economy 7-style setups) is required or compatible.
- Export / solar: if you have solar PV/battery, check how the import tariff interacts with export payments (SEG).
What to check before you switch
- Free window: exact times, days, and whether they change seasonally.
- Outside-window unit rate: compare against a normal single-rate tariff.
- Standing charge: higher standing charges can wipe out benefits for low users.
- Contract length: fixed vs variable; any exit fees.
- Billing requirements: smart meter readings, app-based billing, or half-hourly consent.
Tip: The fairest comparison is your estimated annual cost using your real usage pattern (or a reasonable estimate of what you can shift). Don’t decide on “free hours” alone.
Compare free-hour tariffs by total cost (not hype)
EnergyPlus compares whole-of-market home energy deals, including tariffs that offer discounted or “free” electricity windows where available. We’ll ask for a few details to match you to options by postcode, meter type and household needs.
If you have an EV
We’ll help you prioritise tariffs where the free/cheap window fits typical overnight charging schedules.
If you don’t
We’ll sense-check whether a simpler tariff may be better unless you can shift usage (laundry, dishwasher, battery).
Privacy: Your details are used to provide your quote and contact you about results. If you prefer, you can ask us not to call and we’ll email your comparison summary.
Get your free-hour tariff comparison
Two realistic scenarios (with numbers)
To help you compare fairly, here are two simplified examples. They’re illustrations only, using rounded numbers and ignoring any standing charge differences. Your exact costs depend on your region, supplier, meter setup and current market rates.
Scenario A: EV owner who can shift a lot
- Annual electricity use: 4,200 kWh
- EV charging + appliances shifted into free hours: 1,600 kWh
- Remaining paid usage: 2,600 kWh
Example maths: If a standard single-rate tariff is 25p/kWh, cost ˜ 4,200 × £0.25 = £1,050 (plus standing charge).
If a free-hours tariff is 0p/kWh in-window and 35p/kWh out-of-window, cost ˜ 2,600 × £0.35 = £910 (plus standing charge). Potentially favourable if standing charges/terms don’t offset it.
Scenario B: Typical household, limited shifting
- Annual electricity use: 2,900 kWh
- Shifted into free hours: 300 kWh (dishwasher/laundry)
- Remaining paid usage: 2,600 kWh
Example maths: Standard at 25p/kWh ˜ 2,900 × £0.25 = £725 (plus standing charge).
Free-hours tariff at 35p/kWh out-of-window ˜ 2,600 × £0.35 = £910 (plus standing charge). In this example, “free hours” would likely cost more overall.
Why we show it this way: The key variable is how many kWh you can move into the free/discount window. If it’s small, a higher out-of-window unit rate can wipe out the benefit.
Compare free-hour tariffs: what matters most
Not all “free electricity hours” offers are alike. Use this table to compare the structure of deals, then validate against your likely usage pattern.
| Tariff structure | Best for | Watch-outs | What to check on the tariff facts |
|---|---|---|---|
| Daily free window e.g. set overnight hours |
EV charging; battery charging; night-time appliance runs | High out-of-window rate; higher standing charge; strict timing | Exact times; unit rate outside; standing charge; exit fee; smart meter requirement |
| Weekend free hours e.g. Sat/Sun blocks |
Families doing laundry/drying; batch cooking | Not much use if you’re out; may not help weekday-heavy users | Which weekend hours count; whether bank holidays count; out-of-window unit rate |
| Dynamic / half-hourly pricing prices change through the day |
Flexible households; tech-comfortable users; automation via smart devices | Prices can spike; requires attention/automation; not “set and forget” | How prices are set; caps/limits; data consent; how you’re notified; billing method |
Decision checklist (quick yes/no)
- Yes — I can shift at least ~20–35% of my electricity use into the free/cheap window (often EV charging).
- Yes — I’m happy to schedule appliances or use timers/smart plugs.
- Yes — I have (or can get) a smart meter and I’m comfortable with half-hourly readings if required.
- No — I’m mostly home in the day and can’t move usage; a standard tariff may suit better.
What to gather for an accurate comparison
- Your latest bill (unit rates + standing charge)
- Annual kWh (electricity, and gas if you have it)
- Your meter type (smart / traditional; single or multi-rate)
- Any big loads: EV, heat pump, tumble dryer, home battery
Costs, exclusions and common pitfalls
These are the issues that most often trip people up when moving to a “free hours” tariff.
1) Standing charge still applies
Even with “free” unit rates during a window, you still pay the daily standing charge. If you’re a low user, this matters a lot.
2) Higher rates outside the window
Suppliers often recoup the cost of free hours with higher daytime/evening rates. Compare annual cost, not just the headline.
3) Smart meter & data consent
Some tariffs require half-hourly readings. If you opt out, you might not be eligible or you may be moved to a different tariff.
4) Exit fees and fixed terms
Fixed deals can include exit fees. If you’re likely to move home or change circumstances soon, factor that in.
5) Appliance timing & noise
Running appliances overnight can be inconvenient (or noisy). Make sure the “free” window fits your household and neighbours.
6) “Free” is electricity only
If you have gas, it won’t usually be “free”. Check whether you’re switching electricity only, or both fuels.
Safety note: If you schedule appliances to run unattended, follow manufacturer guidance (especially tumble dryers) and keep ventilation and fire safety in mind.
FAQs: free electricity hours tariffs (UK)
Are free electricity hours actually free?
During the specified window the unit rate may be 0p/kWh, but you’ll still pay the standing charge. Outside the window, rates may be higher to balance the offer.
Do I need a smart meter for a free-hours tariff?
Often, yes—especially if the supplier needs half-hourly readings to apply the free window accurately. Some suppliers may offer similar deals with other meter setups, but availability varies.
Can I get a free-hours tariff on prepayment?
Sometimes, but many specialist tariffs are Direct Debit only. It depends on the supplier, your meter, and whether smart prepay is supported. We’ll filter by what’s available for your setup.
Will the free hours match Economy 7 times?
Not necessarily. Economy 7 typically has a set off-peak period defined by your meter and region, but “free hours” windows are defined by the supplier’s tariff terms and may differ.
If I have solar panels, do free-hours tariffs still help?
Potentially. If you generate a lot during the day, a tariff with higher daytime rates may matter less. But check how it interacts with your export payments (SEG) and whether you can shift battery charging into the free window without reducing valuable export.
Are there exit fees?
Some fixed tariffs include exit fees; variable tariffs usually don’t, but can change price. Always check the tariff information label or key terms before you switch.
Can the supplier change the free-hour window?
It depends on the tariff type and terms. Fixed tariffs should define the window clearly for the fixed period; dynamic tariffs may vary. Read the terms and how you’ll be notified of changes.
What’s the best way to compare these tariffs?
Estimate how many kWh you can put into the free window (EV charging is the big one), then compare the annual cost including standing charge and any exit fees. If you’re unsure, compare a “best case” and “realistic” case.
Trust, methodology and sources
Page ownership
- Written by: EnergyPlus Editorial Team
- Reviewed by: Energy Specialist
- Last updated: February 2026
How we assess free-hour tariffs (our approach)
We assess “free electricity hours” tariffs using a total-cost lens and a usage-pattern lens:
- Total cost: We compare estimated annual cost using unit rates + standing charge, not just the free window.
- Eligibility: We check constraints that commonly affect UK households: region, payment method, smart meter/half-hourly requirements, and contract terms (including exit fees).
- Real-world usability: We consider whether the free window is practical for typical loads (EV charging, laundry, dishwashing) and whether automation is needed.
- Risk flags: We highlight where higher out-of-window rates, variable pricing, or complex terms could increase bills unexpectedly.
Assumptions & limitations (important)
- Example scenarios use simplified unit rates and exclude standing charge differences to show the impact of shifted kWh. Real tariffs include both.
- Tariff availability can change quickly and may be restricted by region, meter type, and supplier policy.
- Dynamic/half-hourly tariffs can vary day-to-day; past prices don’t guarantee future prices.
- Your ability to shift usage depends on your household routine, appliance loads, EV charger settings, and (where relevant) battery controls.
Sources (UK)
- Ofgem (UK energy regulator) — guidance on switching, tariffs and consumer protections.
- Citizens Advice: Energy — practical advice on bills, meters and switching.
- GOV.UK — official government information (including energy and consumer topics).
Ready to see whether free-hour tariffs stack up for your home?
Get a comparison based on your postcode and setup, with clear notes on eligibility, exit fees and the real trade-offs behind “free” electricity hours.
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