Samsung heat pump: the best electricity tariff to pair with it in 2026
Samsung heat pumps are widely installed across the UK, particularly the EHS monobloc and split ranges. They have capable built-in scheduling and SmartThings integration — which means they align well with time-of-use tariffs. The right tariff depends on whether you're using the built-in controller alone or have SmartThings or Home Assistant in the mix.
Samsung EHS: scheduling capability
Samsung's EHS (Eco Heating System) range supports time-based scheduling through its MIM-E03CN controller or the SmartThings app:
MIM-E03CN wired controller: Supports daily and weekly heating and hot water schedules with target temperatures per time period. Sufficient for fixed-window tariffs (Cosy Octopus, E.ON Next Pumped, British Gas Heat Power).
SmartThings integration: Samsung's smart home platform. Connects the heat pump for remote monitoring and control, scene-based automation, and integration with other Samsung devices. Allows phone-based schedule management and simple automations.
Home Assistant via SmartThings API: A community-developed integration enables more sophisticated automations — triggering hot water during cheapest Agile slots, pausing during peak rates. Less plug-and-play than some competitors but functional for confident HA users.
Tariff recommendations for Samsung EHS owners
Cosy Octopus — works well with MIM-E03CN
The MIM-E03CN's scheduling is adequate for Cosy's three windows. Suggested setup:
- Hot water: 04:30 start, 06:45 end. Add a 13:15 top-up if daily demand is high.
- Space heating: elevated target 03:00–15:30, then minimum 16:00–19:00 (peak window).
Check that Samsung's quiet mode or eco mode settings don't defer operation out of the cheap window — worth verifying the unit actually runs when the schedule calls for it.
SmartThings advantage on Cosy: you can create "Peak mode" and "Cheap rate mode" scenes in SmartThings, toggled manually or automated via routines. If you have other SmartThings devices, coordinating their operation with the peak window is straightforward.
E.ON Next Pumped — good without tight scheduling
Next Pumped's 21-hour below-cap structure means most run-time falls in a cheaper band by default. The super off-peak (22:00–06:00) covers overnight hot water; the off-peak rate (06:00–16:00) covers daytime heating at below-cap rates. For Samsung owners who don't want detailed scheduling, Next Pumped delivers meaningful savings without precision.
Octopus Agile — for Samsung + Home Assistant users
With the Samsung EHS integrated into Home Assistant via SmartThings, Agile automations become practical. An automation that triggers hot water during the day's cheapest 3–4 Agile slots — published each afternoon — can achieve effective rates competitive with or below Cosy's off-peak average. The barrier is setup complexity; if you're starting from scratch, Cosy with the built-in scheduler is the simpler path to similar savings.
The flow temperature point
Many Samsung EHS installations in the UK run at fixed flow temperatures of 45–55°C, particularly where they replaced a gas boiler without radiator upgrades. At those temperatures, COP drops significantly — typically 2.2–2.8 rather than the 3.0–3.5 achievable at 35–40°C.
If your Samsung EHS is running at a high fixed flow temperature, reducing it (or enabling weather compensation mode) is likely to save more than any tariff optimisation. Every 10°C reduction adds approximately 0.5–1.0 to your SCOP. At Q3 2026 rates, that's hundreds of pounds per year regardless of which tariff you're on.
Check your current flow temperature on the MIM-E03CN directly, and confirm with your installer whether weather compensation is active.
Worked example: Samsung EHS 8kW, 4-bedroom detached
- Annual consumption (heat pump + hot water): ~7,800 kWh
- SCOP: ~2.9 (some flow temperature headroom available)
- Controller: MIM-E03CN with basic weekly schedule
Cosy Octopus, 65% shifted, peak mostly avoided (Q3 2026):
- Effective blended rate: ~19.5p/kWh
- Annual cost: ~£1,521
- Saving vs standard variable (26.1p): ~£515/year
E.ON Next Pumped, natural usage pattern:
- Effective blended rate: ~21p/kWh
- Annual cost: ~£1,638
- Saving vs standard variable: ~£398/year
Improving SCOP from 2.9 to 3.3 (via flow temperature reduction) would reduce consumption to ~6,850 kWh — saving a further ~£190/year on top of any tariff optimisation.
Compare every tariff for your home and region on Heat Pump Tariffs — using your actual half-hourly data.