UK energy suppliers with free electricity hours (tariffs explained)
A practical UK guide to “free electricity hours” tariffs: who offers them, how they really work, the catches to watch for, and how to compare them against standard and off-peak deals.
- See which UK tariffs can include free or zero-unit-rate hours (and what “free” usually means)
- Work out if your meter, payment method and usage pattern are eligible
- Use our checklist and examples to decide whether you’d likely be better off on a different tariff
Information is UK-focused and editorially reviewed. “Free hours” terms vary by supplier, region and meter type. Always check the tariff factsheet before switching.
Fast answer: do UK suppliers offer “free electricity hours”?
Sometimes, yes — but in the UK it’s more accurate to think of these as time-based promotions or tariffs where the unit rate is reduced to 0p/kWh (or close to it) for set hours, while the unit rate outside those hours can be higher. You still usually pay a daily standing charge.
Important: “Free” rarely means your whole bill is free. Most deals still include a standing charge and may have higher peak rates. Whether you save depends on how much electricity you can shift into the free window.
Key takeaways
- Smart meter often required to measure time-of-use accurately.
- These are best for flexible usage (washing, tumble drying, dishwasher, EV charging, immersion heating where appropriate).
- Always compare the peak unit rate + standing charge, not just the free window.
What to check first
- Your meter
- Smart meter preferred; some legacy Economy 7 setups may limit options.
- Your payment method
- Some tariffs are direct debit only; prepayment can be restricted.
- Your region
- Rates vary by distribution region; “best” tariff in one area may not be in another.
Quick decision
If you can reliably shift 25–40%+ of your electricity into the free/cheap window, it can be worth investigating. If your usage is mostly evenings (cooking, heating, lighting) and you can’t move it, a standard fixed or competitive tracker may be better value.
How “free electricity hours” tariffs work in practice
In the UK, these tariffs usually fall into one of these patterns:
1) Promotional “free hours” windows
A supplier offers a set number of hours where the unit rate is 0p (or heavily discounted). Outside those hours, the unit rate may be higher than a standard tariff to balance the overall cost.
2) Time-of-use tariffs (cheap off-peak rather than “free”)
Often aimed at EV owners or smart-home users. You get very low off-peak rates (not necessarily free), plus higher peak rates. These can outperform “free hours” if the off-peak window is longer and reliably cheap.
3) Bundle/perk tariffs (credit or reward style)
Occasionally, “free” is marketed as a perk (e.g., bill credit, weekend reward, or app-based challenge). These are harder to compare; the safest approach is still to compare the annual cost estimate for your usage.
Plain-English rule: if the peak unit rate is meaningfully higher, you need enough usage in the free/cheap window to compensate. Otherwise, “free hours” can cost more overall.
Two realistic UK scenarios (with numbers)
These examples are illustrative to show the maths. Actual prices vary by supplier, region and time.
Scenario A: No EV, can shift some laundry
- Annual use: 3,100 kWh electricity
- Can shift into free window: 20% (620 kWh)
- Tariff model: 4 free hours/day; peak unit rate 32p/kWh; free window 0p/kWh; standing charge 55p/day
Estimated electricity cost (units only): 2,480 kWh × £0.32 = £793.60. Standing charge: 365 × £0.55 = £200.75. Total ˜ £994.
If a competitive standard tariff is 24p/kWh with 55p/day standing charge: 3,100 × £0.24 = £744 + £201 = £945. In this scenario, “free hours” could be more expensive unless you can shift more usage or the peak rate is lower.
Scenario B: EV owner charging overnight
- Home electric use (excl. EV): 3,100 kWh
- EV charging at home: 2,000 kWh/year
- Can schedule EV + appliances into free window: 60% total (3,060 kWh in window)
- Same tariff model as above (peak 32p/kWh, free 0p/kWh, 55p/day)
Estimated electricity cost (units only): remaining 2,040 kWh × £0.32 = £652.80. Standing charge: £200.75. Total ˜ £854.
On a 24p/kWh standard tariff: 5,100 × £0.24 = £1,224 + £201 = £1,425. Here, shifting a large chunk of use can make “free hours” look much stronger (but only if you can reliably hit the window and the terms stay the same).
Assumptions: unit rates are examples only; gas not included; standing charge assumed equal for simplicity; no discounts/credits applied; usage split is the key variable.
Compare “free hours” tariffs against the whole market (UK homes)
If you’re considering a tariff with free or very cheap hours, the safest way to decide is to compare it against standard fixed, variable, and other time-of-use options using your postcode and your expected usage pattern.
What we’ll help you compare
- Unit rates and standing charges in your region
- Tariff type: fixed, variable, tracker, Economy 7, time-of-use, EV-focused
- Eligibility and meter requirements (including smart meter needs)
- Exit fees and contract terms (where applicable)
Tip: If you don’t know your annual kWh use, your bill or online account usually shows it. If not, start with an estimate and update later — the key is whether you can shift usage into the right hours.
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Comparison table: free-hours vs other UK tariff types
Use this table to sanity-check whether “free hours” is the right tool for your situation. The best choice depends on your ability to shift usage and your tolerance for price complexity.
| Tariff type | What you get | Typically suits | Common watch-outs |
|---|---|---|---|
| “Free electricity hours” | 0p/discounted unit rate for set hours; higher rate outside; standing charge usually applies | EV owners, flexible households, people who can automate loads | Peak rates can be high; “free” doesn’t remove standing charge; timing may not match your routine |
| Time-of-use (cheap off-peak) | Low off-peak rate for a window (e.g., overnight); higher peak rate | EV charging, storage heaters (where appropriate), smart scheduling | Needs discipline/automation; can cost more if most use is at peak times |
| Economy 7 | Two rates: day and night (night usually ~7 hours, timings vary by region/meter) | Some all-electric homes; legacy setups; storage heating users | Night window timing can surprise people; day rate can be high; not ideal if usage is daytime-heavy |
| Standard fixed | Same rate all day with price certainty for a term | Most households wanting predictable bills | May include exit fees; you could miss out if market prices fall |
| Tracker / variable | Rates can change (daily for some trackers, or whenever supplier updates) | People who can tolerate price changes and want potential downside/upside | Uncertainty; not always best for budgeting; needs monitoring |
Checklist: who free-hours tariffs can suit
- You have (or can get) a working smart meter
- You can shift high-use appliances into the window (or automate)
- You have an EV or can concentrate loads (e.g., laundry days)
- You’re comfortable with a tariff that’s more complex to track
Checklist: who it often doesn’t suit
- Most usage is already in the peak evening period and can’t move
- You’re on (or need) prepayment and options are limited
- You rely on electric heating without a strategy to shift demand safely
- You prefer simple bills and predictable monthly payments
A quick “break-even” way to think about it
If your “free hours” tariff has a higher peak unit rate than a standard tariff, you need enough kWh in the free window to offset that difference.
Estimated break-even share ˜ (Peak rate - Standard rate) ÷ Peak rate. Example: peak 32p vs standard 24p ? (32-24)/32 = 25%. If you can’t shift roughly that share (or more), it may not stack up.
This is simplified and ignores standing charge differences, tiered rates, credits, and supplier-specific conditions.
Costs, exclusions and common pitfalls (UK-specific)
Before switching for “free hours”, check these points carefully — they’re where people most often get caught out.
Standing charge still applies
Even with 0p unit rates for certain hours, most UK tariffs still charge a daily standing charge (different by region). It can make a big difference for low users.
Peak unit rate can be higher
Many “free hours” designs recover costs by increasing the unit rate outside the free window. If you cook, shower (electric), or heat mostly at peak times, bills can rise.
Eligibility: smart meters & setups
You may need a compatible smart meter and the supplier’s preferred meter configuration. Some multi-rate meters, restricted meters, or complex setups can limit your options.
The “free” window might change
Promotional structures and time windows are set by the supplier and may be updated for new customers or at renewal. Always read the tariff terms and what happens after the initial period.
Exit fees & contract terms
Fixed deals can include exit fees. If you’re testing whether free-hours works for you, check if leaving early would cost money.
Not all “shifting” is safe or practical
Avoid running appliances in ways that increase risk (e.g., unattended tumble drying). Savings should never come at the expense of safety or comfort.
What to do before you switch: ask for (or download) the tariff information / tariff factsheet and check (1) peak unit rate, (2) standing charge, (3) exact free/cheap hours, (4) term length & exit fees, (5) meter and payment eligibility.
FAQs: free electricity hours tariffs in the UK
Do any UK energy suppliers offer genuinely free electricity?
Some suppliers periodically offer tariffs where the unit rate is 0p/kWh for set hours. However, you’ll usually still pay a standing charge, and the unit rate outside those hours may be higher. “Free” is typically limited to a window and subject to conditions.
Do I need a smart meter for free-hours or time-of-use tariffs?
Often, yes. Time-based tariffs generally rely on half-hourly (or similar) readings that smart meters can provide. Some legacy multi-rate meters exist, but eligibility depends on the supplier and your meter configuration.
Are free electricity hours the same as Economy 7?
No. Economy 7 typically has a night rate for around 7 hours (timings vary), but it’s not usually 0p. “Free hours” tariffs are promotions or TOU structures with specific free/discounted windows that can be shorter and may come with higher peak rates.
Can I get a free-hours tariff on prepayment (PAYG)?
Sometimes, but options can be limited. Many specialist time-of-use tariffs are aimed at direct debit customers. If you’re on prepayment, compare what’s available in your region and consider whether switching payment method is suitable for you.
What appliances actually make a difference in the free window?
High-consumption loads make the biggest impact: EV charging, tumble drying, dishwasher, washing machine, and (where safe and appropriate) hot water heating. Kettle use and lighting are relatively small.
Will I definitely save money with free electricity hours?
No. Savings are not guaranteed. Whether you benefit depends on your peak unit rate, standing charge, and how much usage you can shift into the free/cheap hours. Comparing estimated annual costs for your postcode is the most reliable approach.
Do free-hours tariffs affect gas prices too?
Usually not. These offers tend to be electricity-only pricing structures. If you’re dual fuel, still compare the combined cost — sometimes a strong electricity offer is paired with less competitive gas pricing (or vice versa).
What should I look for on the tariff factsheet?
Check the unit rate(s) for each time band, the standing charge, any exit fee, the tariff end date, and any conditions (smart meter requirement, direct debit, EV requirement, app usage, fair use limits, etc.).
Trust, editorial standards & how we assess “free hours” tariffs
Page details
- Written by
- EnergyPlus Editorial Team
- Reviewed by
- Energy Specialist
- Last updated
- April 2026
Our methodology (transparent and UK-specific)
When we assess tariffs marketed as “free electricity hours”, we prioritise what changes your bill in the real world:
- Total cost focus: we compare standing charge + unit rates across time bands, not the headline “free” claim.
- Eligibility checks: smart meter requirements, payment methods (direct debit vs prepayment), and any constraints (EV requirement, app usage, fair-use limits).
- Region sensitivity: rates differ by distribution region; we avoid assuming one national price.
- Behaviour realism: we test whether typical households can actually shift enough kWh (and we highlight where it’s unlikely).
Limitations: Suppliers can change offers and eligibility. The most accurate result comes from comparing deals available at your postcode and reviewing the tariff factsheet before agreeing to switch.
Useful UK sources
- Ofgem (the energy regulator) — regulation, consumer protections, switching rules
- Citizens Advice energy guidance — practical help with bills, switching and complaints
- GOV.UK energy support and services — official programmes and advice
Ready to see if free-hours tariffs are worth it for your home?
Compare available UK home energy deals for your postcode, including time-of-use options. We’ll focus on total estimated cost, not marketing headlines.
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