Engage EV Employee 18m v3 HH vs Sainsburys Fix and Reward Fixed 12m v81

Side-by-side comparison of EDF Engage EV Employee 18m v3 HH and Eon Next Sainsburys Fix and Reward Fixed 12m v81 using real UK smart-meter data.

Make it personal

See which is cheaper for your home

The figures above use a modelled household. Your own saving depends on when you use electricity — run this comparison against your real half-hourly smart-meter readings to see numbers that match your usage.

Bright smart-meter sync or CSV upload — free, no card needed.

Create free account How it works

About these tariffs

EDF
EDF

Engage EV Employee 18m v3 HH

Time of Use
Full details & per-region rates
Eon Next
Eon Next

Sainsburys Fix and Reward Fixed 12m v81

Standard
Full details & per-region rates

Questions

We are still calculating the worked example for this comparison. The page refreshes nightly and will show a side-by-side cost once a full period of data has been modelled. The right tariff depends on usage pattern - shift workable load (EV charging, heat pump cycles, hot water) into the cheaper periods of each tariff to maximise the saving.

Engage EV Employee 18m v3 HH is a time of use tariff from EDF. Sainsburys Fix and Reward Fixed 12m v81 is a standard tariff from Eon Next. They differ in how the unit rate is structured across the day, which is what drives the cost difference for households with shiftable load.

We take a real UK home's half-hourly smart meter data over the previous 90 days and model the bill on each tariff using the supplier's current published rates and standing charges. Standing charges scale with the modelled period; unit rates apply per half-hour using each tariff's rate structure (standard, Economy 7, time-of-use bands, or wholesale-tracking). Full methodology and data sources are linked below.

Both EDF and Eon Next publish per-region rates across the 14 UK DNO areas. Click through to either tariff page below to see the rates and standing charge specific to your DNO. Some tariffs require a smart meter or have other eligibility criteria set by the supplier.

The cost calculation rebuilds every night using current rates. Page caching is one hour so repeat visits within the day are fast. If a tariff's rates change mid-day, you will see the new numbers on the next nightly refresh.

How this comparison is built. Every cost figure on this page comes from modelling real half-hourly UK smart-meter data against each supplier’s current published rates and standing charges. The calculation refreshes nightly. We earn a small commission when a switch completes via a referral link — it does not affect the price you pay.

Read the full methodology Where the data comes from