Switching supplier is the quickest way to change what you pay for the same electricity. It’s free, nobody visits your home, and your supply isn’t interrupted. The part people get wrong is the comparison: a big headline discount can still cost more over a year once standing charges and the post-discount rate are included. This guide shows how to compare properly.
What to have ready
- MPRN — the 11-digit meter point reference number on your bill
- Annual usage in kWh — on many bills, or add up a year
- Your current tariff type — flat, day/night or smart
- Contract end date and any exit fee on your current plan
- If you have solar panels, your current export rate — see selling electricity back to the grid
Step by step
- Compare on a site listed by the CRU as an accredited price comparison service.
- Enter your actual usage — the default estimates rarely match your home.
- Rank offers by estimated annual cost, then read the terms of the top two or three.
- Check the tariff type fits how you use electricity — see is night-rate worth it?
- Sign up with the new supplier, which arranges the change.
- Submit a meter reading on the switch date so your final and first bills are accurate.
- Set a reminder a few weeks before the discount period ends.
Compare a whole year: a worked example
Hypothetical offers for a home using 4,200 kWh a year on a flat tariff. Prices include VAT:
| Offer A | Offer B | |
|---|---|---|
| Unit rate | 30c | 27c |
| Discount | 12% off unit rates for 12 months | None |
| Standing charge | €280 a year | €330 a year |
| Welcome credit | None | €50 |
| Exit fee | €50 if leaving in year 1 | None |
Year 1
- Offer A: 4,200 × €0.30 × 0.88 + €280 = €1,389
- Offer B: 4,200 × €0.27 + €330 − €50 = €1,414
Year 2 (no discount, no credit)
- Offer A: 4,200 × €0.30 + €280 = €1,540
- Offer B: 4,200 × €0.27 + €330 = €1,464
Offer A wins year 1 by €25 — but only if you remember to switch again before year 2, when it costs €76 more. The cheaper option depends on whether you’ll actually compare again. Our tariff calculator runs the same arithmetic for flat versus day/night plans.
Traps to avoid
- Judging on the discount percentage. A large discount on a high unit rate can still lose to a lower undiscounted rate.
- Ignoring the standing charge. It’s paid every day regardless of use — see standing charges explained.
- Forgetting the end of the discount. That’s when many households move to a more expensive standard rate.
- Missing exit fees on fixed-term contracts.
- Choosing a day/night tariff without being able to shift usage into the cheaper window.
- Overlooking your export rate if you have solar: compare the import rate and the export rate together.
After you switch
- Check that the first bill uses your switch-date meter reading.
- Keep your previous supplier’s final bill and confirm any credit is refunded.
- Note the discount end date in your calendar.
For other ways to bring the bill down, see how to reduce your electricity bill.
