When Is the Best Time to Switch Energy Supplier in the UK?

Energy prices fluctuate throughout the year, and with cost-of-living pressures still high, many households are wondering if switching energy supplier can lead to better deals and real savings.

The answer? Yes — but timing and comparison matter.

This guide explains when and how to switch energy supplier in the UK for maximum benefit, including what to watch out for with fixed vs variable tariffs, exit fees, and how to avoid common switching mistakes. Whether you're a renter, homeowner, or student, switching wisely can shave hundreds off your annual bill.

Why Switching Energy Supplier Matters

Many UK households still stick with the same provider year after year — often ending up on expensive standard variable tariffs after an initial deal expires. According to Ofgem, millions of consumers could save money by switching to a better-suited tariff or supplier.

Benefits of Switching:

• Access to cheaper tariffs

• Better customer service

• Fixed-rate protection against price rises

• Greener or more flexible energy plans

• Loyalty rewards or cashback offers

Even if prices are high across the board, switching could still mean moving to a more stable or tailored plan — especially if your current deal is outdated.

When Is the Best Time to Switch Energy Supplier?

There’s no one-size-fits-all date, but certain situations and times of year can maximise savings and ease the switch process.

1. Just Before Your Current Fixed Tariff Ends

• Suppliers typically move you to a standard variable rate when your fixed deal ends — often their most expensive tariff.

• Start comparing 49 days before your contract ends — this is when you can switch without paying exit fees.

2. During the Shoulder Seasons (Spring and Autumn)

• Suppliers often offer more competitive rates when demand is lower.

• You avoid mid-winter delays and high bills.

3. When the Energy Market Stabilises or Prices Drop

• After a spike in wholesale prices, deals may improve.

• Monitor rates over time or sign up for alerts via comparison sites.

4. If You're Moved to a Supplier After a Provider Collapse

• Ofgem assigns a new supplier if yours fails, but the tariff you're placed on might not be the best.

• You’re free to switch as soon as your new account is set up — no fees apply.

Read our guide on: How to Switch Energy Suppliers in the UK

How to Compare Energy Deals Effectively

Use trusted UK comparison tools such as:

• MoneyHelper's guide to switching

• Ofgem-accredited comparison sites

When comparing, look at:

• Unit rate (price per kWh for electricity/gas)

• Standing charge (daily fee regardless of usage)

• Tariff type (fixed or variable)

• Exit fees (charged if you leave early)

• Payment method (some tariffs favour direct debit)

• Green energy credentials (for eco-conscious households)

Fixed vs Variable Tariffs: Which Should You Choose?

Fixed Tariffs

• Lock in a rate for 12–24 months

• Protects against price rises

• May include early exit fees

Variable Tariffs

• Move with market prices

• No exit fees in most cases

• Prices can rise unexpectedly

Tip: Fixed deals are best when rates are low or stable. If prices are likely to fall, variable may offer more flexibility.

Common Mistakes to Avoid When Switching

Avoiding these pitfalls ensures your switch saves you money rather than costing you more:

Switching too early and incurring exit fees

Always check your contract end date and exit fee terms before switching.

Ignoring standing charges

A lower unit rate can be offset by high daily charges — compare both.

Missing cashback or referral offers

Some tariffs include sign-up bonuses or partner offers — but read the terms carefully.

Not submitting a meter reading

This can lead to billing errors when switching. Always submit an accurate reading before and after your switch.

Switching to an unfamiliar supplier without checking reviews

Use Citizens Advice’s comparison tool to view service ratings and complaint records.

Unique Tip: Align Your Switch with a Budgeting Review

When you’re reviewing your household budget (monthly or quarterly), it’s a good time to assess your energy costs too. Use the MoneyHelper Budget Planner to identify high-cost areas — then consider switching your energy supplier as part of a broader savings plan.

This approach ensures switching isn’t treated in isolation but is part of a larger money-saving mindset.

Read our guide on: Energy Saving Tips for UK Homes

Can Renters and Students Switch Suppliers?

Yes — but with a few caveats.

Renters

• If you're responsible for paying the energy bills directly, you can switch.

• It’s good practice to notify your landlord — but they can’t stop you switching unless they pay the bills themselves.

Students in Shared Houses

• One tenant (usually the bill-payer) can initiate the switch.

• Choose a fixed tariff to avoid disputes or surprises if someone moves out.

How Long Does It Take to Switch Energy Supplier?

The energy switch process typically takes 5 working days. You won’t be cut off during the switch, and there’s no need to contact your old supplier — your new provider will handle the handover.

You’ll usually get a 14-day cooling-off period, during which you can cancel the switch without penalty.

Is It Worth Switching to a Green Energy Supplier?

Green tariffs supply electricity from renewable sources like wind and solar. They may be:

• Priced similarly to standard tariffs

• More transparent about carbon offsetting

• A way to reduce your environmental impact

Use the Green Energy Guide from the Energy Saving Trust to compare providers and credentials.

FAQs: Switching Energy Suppliers in the UK

When can I switch energy suppliers without penalty?

Up to 49 days before your fixed tariff ends — suppliers can’t charge exit fees within this period.

Will I be without power during the switch?

No — there’s no interruption in your energy supply when switching.

Can I switch if I'm in debt with my supplier?

Yes, if your debt is under £500 and you're on a prepayment meter. Otherwise, you may need to clear your balance first.

Can smart meters affect switching?

Most SMETS2 smart meters retain functionality when you switch. If you have a first-gen (SMETS1) meter, it may lose smart features temporarily.

Read our guide on: What Is a Smart Meter and Should You Get One?

Will I get a final bill?

Yes, your old supplier will send a final bill — based on your closing meter reading — after your switch is complete.

Final Thoughts: Switch Smart, Save More

Switching your energy supplier isn’t just a one-time trick — it’s a key habit in smart financial management. Timing your switch correctly, comparing thoroughly, and avoiding common mistakes can lead to significant savings over the year.

With comparison tools and switching protections in place, there’s never been an easier time to make the move — or a better time to take control of your bills.

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