What are ‘free electricity hours’ energy tariffs in the UK?

Free electricity hours tariffs are UK energy deals that offer zero (or heavily discounted) unit rates for electricity during set off-peak hours. You typically pay a higher rate at other times, so they work best if you can shift a meaningful portion of your usage into the free-hours window (for example, EV charging, tumble drying, washing machine cycles, dishwashers, immersion heaters or heat pumps).

Are free electricity hours tariffs actually cheaper than standard tariffs?

They can be cheaper, but only if your household can move enough electricity use into the free hours to outweigh any higher peak unit rates and standing charges. A quick way to assess this is to estimate your average kWh you can shift into the free period and compare your projected monthly cost to your current tariff. For a tailored comparison, use the guidance and tools on EnergyPlus.

Who benefits most from tariffs with free electricity hours?

These tariffs are often most cost-effective for households with high, flexible electricity usage—especially EV owners, homes using overnight charging, properties with smart appliances, or anyone able to run energy-intensive appliances during the free window. They can also suit households that can schedule heating or hot water in off-peak periods (where safe and compatible with your system).

Do I need a smart meter to get a free-hours electricity tariff?

In most cases, yes. Free-hours and time-of-use tariffs generally require a working smart meter so your supplier can accurately record consumption by time band. If you don’t have a smart meter, check eligibility with your supplier or consider arranging an installation before switching.

When are the free electricity hours (and do they change)?

The free-hours window varies by supplier and tariff and is set out in the tariff terms. Some deals offer fixed free periods each day, while others may vary by day of the week or be linked to wholesale prices. Always confirm the exact times in writing before switching, and set reminders or automation so you consistently use energy during the free period.

What’s the catch with ‘free electricity’ tariffs?

The most common trade-off is higher electricity unit rates outside the free hours (and sometimes higher standing charges). Some tariffs may also be variable, have exit fees, or require direct debit and smart meter eligibility. To avoid overpaying, estimate your peak vs off-peak usage and compare total monthly costs—not just the free-hours headline.

Can I run appliances overnight safely to take advantage of free hours?

You can use timers and smart plugs to schedule appliances, but always follow manufacturer guidance and safety advice. Avoid running appliances unattended if the manufacturer recommends supervision, ensure good ventilation (especially for tumble dryers), and never overload extension leads. If you’re unsure, prioritise lower-risk loads and consult the appliance manual.

Will a free-hours tariff work if I don’t have an EV?

Yes, but the savings may be smaller unless you can shift other high-usage activities into the free period (laundry, dishwashing, batch cooking with electric ovens, hot water heating, or charging home batteries). The key is whether enough kWh can reliably move into the free window each week.

How do I choose the best free electricity hours tariff for my home?

Start by reviewing your current usage (kWh) and identifying what can be scheduled into off-peak time. Compare: (1) free-hours schedule, (2) peak unit rate, (3) standing charge, (4) tariff type (fixed vs variable), (5) exit fees and contract length, and (6) any requirements (smart meter, EV, direct debit). Use the EnergyPlus guide to shortlist options and validate the total annual cost for your usage pattern.

Where can I get more help comparing UK energy tariffs with free electricity hours?

Read the full guide on EnergyPlus for practical cost-saving advice, key checks before switching, and tips to maximise savings from free-hours periods: https://www.energyplus.co.uk/CostSavingAdvice/best-energy-tariffs-with-free-electricity-hours-uk

Best energy tariffs with free electricity hours in the UK

A practical UK guide to "free electricity hours" tariffs (including EV and smart tariffs): how they work, what to watch for, and how to check if they’re actually cheaper for your home.

Understand peak vs free-hour unit rates (and why “free” isn’t always best)
Check eligibility: smart meter, region, payment method, EV requirements
See realistic examples with numbers and a quick suitability checklist

Get your energy quote How free-hours tariffs work

Figures are illustrative and depend on your region, meter type, usage pattern and tariff terms. Always check the tariff’s unit rates, standing charge and eligibility.

Fast answer: are “free electricity hours” tariffs worth it?

They can be worth it if you can reliably move a meaningful chunk of electricity use into the free window (often overnight or set hours at weekends). But many of these tariffs have higher peak unit rates and/or standing charges, so the best option depends on your usage pattern, meter type, and whether you can automate demand (EV charging, battery, heat pump, appliances on timers).

Key takeaway: Don’t judge on the “free hours” headline. Compare the whole day: peak unit rate(s), off-peak rate(s), standing charge, exit fees, and any eligibility rules.

Usually suits

EV owners who can schedule charging overnight (or at set free hours)
Homes with a battery (or flexible appliances on timers)
Higher electricity use households able to shift usage (dishwasher, washing, tumble dryer)
People comfortable with smart meter data and time-of-use pricing

Often not ideal for

Low electricity use homes (standing charge dominates)
People home all day using electricity at peak times
Homes without a smart meter (many tariffs require one)
Anyone who can’t practically shift demand (e.g., rented property without timers/controls)

Check eligibility & compare tariffs See the comparison table

How “free electricity hours” tariffs work (UK)

In the UK, “free electricity hours” is typically a time-of-use (TOU) offer. Instead of one flat unit rate, you get:

Free (0p) unit rate for a set time window (e.g., overnight, weekends, or specific hours)
Peak (higher) unit rate outside the free window
Sometimes an additional off-peak rate (cheap but not free) for other hours
A daily standing charge that always applies

Your total cost depends on how much electricity you use in each time band. The tariff may still be a poor deal if most of your usage happens outside the free window.

Common UK eligibility rules

Smart meter: Often required (half-hourly readings). Some suppliers won’t offer TOU without it.
Payment method: Many are direct debit only. Prepayment options can be limited.
Region/network: Unit rates and standing charges vary by electricity distribution region.
EV/charger requirements: Some EV-focused tariffs require an EV, compatible charger or app integration.

Tip: If you’re on Economy 7/Economy 10 or have storage heating, check whether switching could affect how your meter is billed.

What to compare (the “free hours” checklist)

Exact free window: days/times, and whether it changes seasonally
Peak unit rate: p/kWh outside the free hours
Any off-peak (non-free) rate: and when it applies
Standing charge: p/day (often a major driver of cost)

Contract term: fixed or variable, and any exit fees
Price cap context: variable tariffs can change (cap is not a fixed bill)
Metering/billing: smart meter requirement and half-hourly consent
Who can use it: EV-only, dual fuel required, app-only management, etc.

Compare free-hours tariffs across the market

Tell us a few basics and we’ll match you with tariffs that fit your meter type, region and preferences—including options with free-hour windows where available.

What helps most: your postcode (pricing region) and whether you have (or can get) a smart meter. If you have an EV or battery, mention it in your call.

What happens next

We check tariff availability for your postcode and meter type.
We compare total estimated cost using your details (not just the free window headline).
If you choose to proceed, we’ll guide you through the switch with your chosen supplier.

Prefer to read first? Use the table below to understand which type of free-hours tariff fits your routine.

Get your quote

Compare “free electricity hours” tariff types (what to choose)

Suppliers brand these differently, but most UK “free hours” offers fit into a few patterns. Use this table to pick the structure that matches your routine, then compare actual rates for your postcode.

Tariff type	Typical free window	Best for	Main watch-outs
Overnight free hours (EV-style)	Set hours overnight (e.g., 2–6 hours)	EV charging, battery charging, timers for appliances	Higher daytime unit rate; may require EV/compatible charger/app; check standing charge
Weekend free hours	Set hours on Sat/Sun	Families who do laundry/cooking in bulk at weekends	If you’re out weekends, benefit drops; peak weekday rates may be higher
“Free period” promo (limited-time)	Free hours for a promotional period	Short-term flexibility while you trial TOU	Price may change after promo; check what you’ll pay later and any exit fees
Multi-rate TOU (cheap off-peak, not necessarily free)	Several bands across day/night	People who can shift some use but want less “all-or-nothing” free window	Complex; needs smart meter; compare your split across bands carefully

Decision checklist (quick self-assessment)

If you answer “yes” to 3+…

I can schedule EV charging / battery charging overnight
I can run laundry/dishwasher during the free window
I’m happy to use timers / smart plugs to automate appliances
I have a smart meter (or I’m willing to get one installed)
I understand my usage (or can review it monthly)

Avoid or be cautious if…

Most usage is evenings/weekday daytime and can’t move
You rely on electric heating at peak times (unless you can pre-heat/store)
You’re in a fixed deal with high exit fees
You have a complex meter setup (e.g., legacy Economy 10) and aren’t sure how it’ll be billed
You want absolute bill certainty (TOU rewards behaviour; it isn’t “set and forget”)

Two realistic scenarios (with numbers)

These examples show the mechanics of free-hours tariffs. They’re not a promise of savings. Rates vary by supplier, region and time, and some tariffs include more than two bands.

Scenario A: EV driver who can shift charging overnight

Assumptions (illustrative): 3,600 kWh/year electricity total. A “free 4 hours overnight” tariff where daytime is 34p/kWh, free window is 0p/kWh. Standing charge ignored for simplicity (it applies to both tariffs and varies by region).

Flat tariff baseline: 27p/kWh for all usage ? 3,600 × 0.27 = £972/year
Free-hours tariff: 1,300 kWh shifted into free window (EV + appliances), 2,300 kWh at 34p ? 2,300 × 0.34 = £782/year

What to learn: The more you can shift, the more the “free” period matters. But if your peak rate is much higher, small shifting may not offset it.

Scenario B: No EV, limited ability to shift usage

Assumptions (illustrative): 2,900 kWh/year electricity. Same “free 4 hours overnight” tariff (34p peak, 0p free). Flat tariff baseline 27p/kWh. Standing charge ignored for simplicity.

Flat tariff baseline: 2,900 × 0.27 = £783/year
Free-hours tariff: only 350 kWh moved to free window, 2,550 kWh at 34p ? 2,550 × 0.34 = £867/year

What to learn: If you can’t shift much, a higher peak rate can outweigh the free window.

To do this for your home, you need your estimated annual kWh and a rough idea of how much you can move into the free hours. If you have a smart meter, you can often view half-hourly usage in your supplier app.

Costs, exclusions and common pitfalls (UK-specific)

1) Peak rates can be much higher

Some “free hours” tariffs recover the cost via higher unit rates outside the free window. If your usage is mainly evenings, you may pay more overall.

2) Standing charges still apply

“Free” refers to the unit rate for certain hours—not your daily standing charge. If you use little electricity, standing charge can dominate the bill.

3) Smart meter and data sharing

TOU tariffs typically require half-hourly readings. Check what you’re consenting to and how billing works if smart readings fail.

4) EV-only requirements (some tariffs)

Certain deals are restricted to EV drivers or require a compatible charger/app. If you change vehicle or charger, check whether you can stay on the tariff.

5) Exit fees and contract terms

Fixed tariffs may include exit fees. Also check if the “free hours” feature is time-limited or can be changed with notice.

6) Economy 7 / complex meter setups

If you have Economy 7/Economy 10 or storage heating, confirm how your new supplier will bill your registers and whether the tariff is compatible.

Simple check before switching: Ask “What will my peak unit rate be, what’s the standing charge, and how many kWh can I realistically move into the free hours each week?” If you can’t answer, get a quote based on your usage.

FAQs: free electricity hours tariffs (UK)

Are free electricity hours tariffs really 0p per kWh?

Some tariffs set the unit rate to 0p during specific hours, but you’ll still pay the standing charge and any usage outside those hours at the peak rate. Always read the tariff’s unit rate schedule and terms.

Do I need a smart meter in the UK?

Usually, yes. Time-of-use billing typically relies on smart meter readings (often half-hourly). If you don’t have one, ask whether the supplier will install a smart meter and what happens if smart readings aren’t available.

Can tenants switch to a free-hours tariff?

If you pay the energy bills and your name is on the account, you can usually switch. If a landlord includes bills or controls the supply, you may not be able to. For smart meter installations, you may need permission depending on tenancy terms.

What if I’m on a prepayment meter?

Availability can be more limited, especially for smart TOU tariffs. It’s still worth checking: some suppliers support smart prepayment, but not all offer “free hours” features on prepay.

Will switching affect my Economy 7 or storage heating?

It can. Economy 7/Economy 10 and storage heating setups can be sensitive to how registers are billed. Before switching, confirm how the new tariff handles your meter and whether you’ll keep separate day/night rates (or move to a different TOU structure).

Are these tariffs capped by the Ofgem price cap?

The Ofgem price cap applies to certain default/standard variable tariffs, but TOU structures may work differently. Even where a cap applies, it’s not a cap on your total bill—your bill depends on usage and the tariff’s rates and standing charge.

How do I estimate if it’ll be cheaper for me?

Start with your annual electricity use (kWh). Estimate the portion you can move into the free window (EV charging is the biggest lever). Then compare: (peak kWh × peak rate) + (other band kWh × other rate) + (standing charge × 365). We can do this comparison for your postcode and usage pattern.

Can the free hours change?

Depending on the supplier and product, time windows and rates may change (especially on variable tariffs). Check the contract and product terms for notice periods and whether the free-hour feature is guaranteed for the tariff’s term.

Trust, methodology and sources

Page ownership

Written by: EnergyPlus Editorial Team
Reviewed by: Energy Specialist
Last updated: February 2026

How we assess “best” free-hours tariffs

We treat “best” as best-fit for your household, not one universal winner. When comparing tariffs with free electricity hours, we focus on:

Total estimated annual cost using the tariff’s time bands + standing charge (region-specific)
Practical eligibility (smart meter, direct debit, EV/charger requirements, app dependency)
Risk and flexibility (fixed vs variable, exit fees, how often rates/time windows can change)
Clarity (is the free window clearly defined and easy to use/automate?)

Limitations: We can’t know your exact half-hourly usage without smart meter data or your supplier/app export. Any example calculations on this page are illustrative and exclude supplier-specific extras.

Useful UK sources

Ofgem – regulator guidance on tariffs, switching and consumer protections.
Citizens Advice: Energy – help with bills, switching, complaints and billing issues.
GOV.UK: Energy – official guidance and support schemes information.

Ready to see if free-hours electricity is a good fit?

We’ll compare whole-of-market options for your postcode and highlight any free-hour tariffs you’re eligible for—based on rates, standing charges and your setup.

Get your energy quote Re-check the suitability checklist

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Updated on 24 Feb 2026