Cheapest fixed energy deal for a new build in the UK
Find the cheapest fixed energy deal for your new build by comparing whole-of-market options for your exact postcode, meter type and payment method—then choosing the fix length and exit fees that fit your plans.
- New-build ready: smart meters, electric heating and EV-friendly homes
- See live fixed deals (where available) matched to your property details
- Understand standing charges, exit fees and eligibility before you commit
Estimates only. Availability and prices vary by postcode, meter type, payment method and credit checks. Always check tariff terms, including exit fees and standing charges.
Fast answer: cheapest fixed energy deal for new build UK
The cheapest fixed energy deal for new build UK homes is the fixed tariff with the lowest total estimated annual cost for your exact postcode and usage—not simply the lowest unit rate. New builds often have smart meters and different heating/EV loads, so the “cheapest” fix depends on standing charges, exit fees, fix length and whether you pay by Direct Debit.
What usually makes a fix “cheapest”
- Low total cost after standing charge is included
- Reasonable exit fees if you may move again
- Correct meter type (smart / credit / prepay)
New-build details that matter
- Electric heating (heat pump) vs gas boiler
- EV charging patterns (overnight vs daytime)
- Developer-provided meter point IDs (MPAN/MPRN)
If you want a safe rule of thumb
Compare 12‑month and 24‑month fixed options and choose the one with the lowest estimated annual cost and exit fees you can live with. If you’re unsure, prioritise flexibility.
Important: We don’t publish “the cheapest tariff” as a single named deal because prices change daily and vary by region, meter, payment method and eligibility. Use the quote journey to see live fixed deals for your new build.
How to find the cheapest fixed deal (new build step-by-step)
New builds can be slightly trickier to switch because addresses aren’t always recognised straight away and you may have a smart meter from day one. These steps keep it simple and avoid the common delays.
- Get your meter details: if you’ve just completed, ask the developer/letting agent for your MPAN (electricity) and MPRN (gas) and your move-in date.
- Estimate your usage: if you don’t have bills yet, use realistic annual kWh (we show examples below) and adjust for EV charging or electric heating.
- Compare fixed terms like-for-like: check the estimated annual cost includes standing charges and that the tariff fits your payment method (Direct Debit, pay on receipt, or prepayment).
- Check exit fees and “moving home” rules: if you might move again within 12–24 months, make sure fees won’t wipe out the benefit of fixing.
- Confirm meter compatibility: smart meters are usually fine, but some properties have electric-only setups or complex meters that limit options.
If your address won’t validate: use your postcode and select the closest match (or proceed with meter IDs if available). In some new developments, it can take a little time for databases to fully update.
Two realistic “new build” cost scenarios (illustrative)
These are worked examples to show how the cheapest fixed deal can change depending on usage. Numbers below are placeholders for method only (not real tariff rates). Your quote will use live market prices for your postcode.
Scenario A: new-build flat, gas + electric
- Assumptions
- 1–2 occupants, gas boiler. Annual usage: 1,800 kWh electricity + 7,000 kWh gas. Paying by Direct Debit. No EV.
- What often makes the cheapest fix
- A fix with a competitive standing charge (because usage is modest) and low/zero exit fees if you might move again.
Scenario B: new-build house, heat pump + EV
- Assumptions
- 3–4 occupants, electric heating/heat pump. Annual usage: 6,000–9,000 kWh electricity. EV charging adds ~2,000–3,000 kWh/year depending on mileage.
- What often makes the cheapest fix
- A fix with strong overall unit pricing and an EV/usage pattern that suits your lifestyle; standing charge matters less when usage is high, but it still counts.
Compare fixed deals for your new build
Enter your details to see available fixed tariffs for your postcode and meter setup. We’ll show estimated annual costs so you can judge what’s genuinely cheapest for you.
New build switching checklist (quick)
- Do you have your move-in date and current supplier details?
- Can you confirm smart / credit / prepayment meter type?
- Do you expect EV charging or electric heating?
- Will you likely move again within the fix period?
Compare fixed-deal options for new builds (what to look at)
When people say “cheapest fixed deal”, they often mean “lowest unit rate”. In practice, the cheapest option for a new build is the one with the lowest estimated annual cost for your usage after standing charges and fees.
| What you’re comparing | Why it matters in a new build | What to do |
|---|---|---|
| Estimated annual cost | Captures unit rates + standing charges using your kWh. New builds can have unusual loads (EV/heat pump). | Use the lowest total cost as your shortlist, then check the next rows. |
| Standing charges | A high standing charge can make a “cheap” fix expensive if your usage is low (common in well-insulated flats). | If you’re low-usage, weight standing charge more heavily. |
| Exit fees | You may move again (snagging, chain delays, tenancy changes). Exit fees can remove any benefit of fixing. | Prefer low fees if your plans are uncertain. |
| Fix length (12/24 months+) | Longer fixes can bring predictability, but they reduce flexibility if you move or rates fall. | Match term length to how long you’ll stay in the property. |
| Payment method eligibility | Some deals are restricted by payment type (e.g. Direct Debit). Tenants can face different options. | Compare using the method you’ll actually use. |
| Meter type (smart / prepay) | Many new builds have smart meters. Prepay meters can reduce tariff choice. | If you’re on prepay but want more choice, ask about changing meter type (where feasible). |
Who a fixed deal often suits (new build)
- You want predictable bills and will stay put for the fix term
- You can pay by Direct Debit and pass eligibility checks
- You’re comparing on total annual cost, not just headline rates
Who should be cautious
- You may move again within 12 months (or the property is still being snagged)
- You’re unsure about your likely usage (first winter in the home)
- You’re on prepay and need maximum flexibility
Costs, exclusions and common new-build pitfalls
These are the issues most likely to stop a “cheap fix” being cheap in real life. They’re especially relevant when you’ve just moved into a new build and don’t yet have a full year of bills.
1) Standing charges can dominate low usage
If your home is efficient and you’re out a lot, unit rates matter less than the daily charge. Always compare based on estimated annual cost.
2) Exit fees vs moving home
Some fixed deals include exit fees. If you might move, a slightly higher tariff with lower fees can be the cheaper outcome.
3) Address & meter registration delays
Sometimes your full address isn’t recognised immediately. Having MPAN/MPRN helps, and you may need to allow a short window after completion.
4) Smart meter mode (SMETS1/SMETS2)
Smart meters should continue to work when you switch, but functionality can vary. Your supplier can confirm how readings will be taken.
5) Heat pumps & EVs change “best value”
If your new build is electric-heavy, the best value is often the deal that performs well at higher kWh—not necessarily the one that looks cheapest for average use.
6) Tenancy rules & landlord controls
Tenants can usually choose their supplier, but there may be rules around meter changes or communal systems. Check your tenancy agreement.
Not sure what you’re currently on? When you move into a new build, you’ll normally start on the supplier serving the property (often on a standard variable tariff). You can switch—just take meter readings on move-in day and keep them for your records.
FAQs: cheapest fixed energy deal for new builds
Can I switch energy supplier immediately after moving into a new build?
Usually, yes. Take opening meter readings on move‑in day and make sure your account is set up with the current supplier first. If the address isn’t fully registered yet, you may need MPAN/MPRN details or a short wait before a switch can complete.
Why do fixed energy prices vary by postcode in the UK?
Energy networks and regional charges differ across Great Britain, and suppliers price tariffs accordingly. Your meter type and payment method can also change what deals you’re eligible for, so a tariff that’s cheap in one area may not be cheapest elsewhere.
Is a 24‑month fix cheaper than a 12‑month fix for a new build?
Not always. Longer fixes can be good for budgeting, but the cheapest option depends on live pricing and your plans. If you might move or your usage is uncertain (first winter in a new home), a shorter fix or lower exit fees can be better value overall.
Do new builds have smart meters, and does that affect my fixed deal options?
Many new builds are fitted with smart meters. In most cases you can still choose from fixed deals, but you should confirm how readings will be taken after switching. If you’re on a prepayment meter, your choice of tariffs may be more limited.
What if my new-build address isn’t showing in comparisons?
This can happen soon after completion. Use your postcode and pick the closest match if available, or use your MPAN/MPRN from the developer or current supplier. If the records haven’t updated, it may take a little time before every database recognises the address.
As a tenant in a new build, am I allowed to choose a fixed tariff?
In most situations, tenants can choose their energy supplier and tariff if they pay the bills. You may need permission for certain changes (like swapping meter type) and communal heating arrangements can be different, so check your tenancy agreement and building setup.
How do I estimate usage for a new build with no bills yet?
Start with a sensible annual kWh estimate based on occupants and heating type, then adjust for high-load items like EV charging or electric heating. You can refine your estimate after your first month or two of smart meter readings, then re-check deals when your usage is clearer.
What should I check in the tariff terms before I fix?
Check the fix end date, exit fees, how prices change (fixed unit rates/standing charges for the term), and any eligibility rules (payment method, meter type). Also confirm what happens if you move home during the fix and whether the tariff can move with you.
Trust, methodology and sources
Page governance
- Written by:
- EnergyPlus Editorial Team
- Reviewed by:
- Energy Specialist
- Last updated:
- July 2026
How we assess “cheapest fixed deal” (transparent approach)
We define the “cheapest fixed energy deal” as the available fixed tariff with the lowest estimated annual cost for a given household—based on the user’s postcode, meter type, payment method and (where provided) usage in kWh.
- We prioritise total cost: estimated annual cost includes unit rates plus standing charges (where applicable).
- We surface key terms: fix length, exit fees and eligibility are treated as decision-critical, not footnotes.
- We reflect uncertainty: new builds may lack historic usage; we encourage updating estimates after the first billing period.
- We don’t publish static “cheapest” winners: tariffs change frequently and differ by region and meter setup.
Limitations: This guide is educational. Your actual prices, availability and acceptance can vary due to credit checks, meter configuration, supplier rules, and whether your new-build address is fully registered on industry databases.
Sources (UK)
- Ofgem (energy regulation, consumer guidance and price cap information)
- Citizens Advice energy advice (switching, billing, and resolving problems)
- GOV.UK (consumer rights and housing-related guidance)
Ready to see the cheapest fixed deals for your new build?
Get postcode-matched fixed tariffs and compare by estimated annual cost, term length and exit fees—so you can pick the deal that’s genuinely cheapest for your household.
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