SmartestEnergy Business (formerly Dual Energy)

Trading

Trustpilot: 4.1 out of 56,103 reviews
Citizens Advice: 879.5 weighted complaints per 10,000 customersApr-Jun 2026 (Q2 2026, non-domestic league, published Sep 2026)
Fuel mix: 7.5% renewable electricityApril 2024 - March 2025 (total company fuel mix: wind 3.8% + biomass/thermal 3.7% + hydro/solar <0.01%)

Dual Energy now trades as SmartestEnergy Business, an active, Ofgem-licensed business electricity and gas supplier based in Worthing and owned by Marubeni. It publishes variable, low-user, deemed and pay-as-you-go price sheets online, with fixed-term contracts of 1-5 years quoted individually. It ranked 12th of 15 ranked suppliers in Citizens Advice's Apr-Jun 2026 non-domestic complaints table and holds a 4.1 Trustpilot score from 6,103 reviews.

Key facts

Legal name: SmartestEnergy Business Limited
Company number: 06468946
Company status: Active (renamed from Dual Energy Direct Limited on 31 Aug 2020)
Incorporated: 10 January 2008
Registered office: Ridgeworth House, 5-9 Liverpool Gardens, Worthing, England, BN11 1RY
Website: https://www.smartestenergybusiness.com
Phone: 01903 703400
Email: quote.business@smartestenergy.com
Ofgem supply licence: Yes
Fuel mix: 7.5% renewable electricity (April 2024 - March 2025 (total company fuel mix: wind 3.8% + biomass/thermal 3.7% + hydro/solar <0.01%))
Trustpilot: 4.1 out of 5, 6,103 reviews
Citizens Advice complaints: 879.5 weighted complaints per 10,000 customers (Apr-Jun 2026 (Q2 2026, non-domestic league, published Sep 2026))
Citizens Advice rank: 12

Tariffs

SmartFix (fixed)
SmartFix renewable (fixed, Carbon Trust-verified renewable)
SmartFix Zero Standing Charge
SmartFlex (variable, no contract / out-of-contract rollover)
Low User (variable, under ~5,000 kWh/yr, electricity)
SmartPay / Advance Pay (pay as you go, electricity)
Deemed (Standard, variable)

Contract lengths: 1 year; 2 years; 3 years; 4 years; up to 5 years (product range stated as 1-5 years)

Smart meters: Yes

Prices

Unit rates: 34p/kWh (SmartFlex electricity, non-half-hourly profiles 1-4, excl. VAT and CCL, effective April 2026); rising to 44p/kWh from 1 Oct 2026. SmartFlex gas (all meters): 3.9p/kWh

Standing charges: 350p/day (SmartFlex electricity, NHH profiles 1-4, effective April 2026; profiles 5-8: 450p/day); 450p/day for profiles 1-8 from 1 Oct 2026. SmartFlex gas: 500p/day

As of 2026-09-24 (sheets effective April 2026; 1 Oct 2026 sheet also published). Price source

Switching

Dual Energy Direct Limited is the same legal entity as SmartestEnergy Business Limited (company 06468946), renamed on 31 Aug 2020; customers were not transferred. Quotes via the online SmartSwitch tool, 01903 259976 or quote.business@smartestenergy.com. SmartFlex customers can leave at any time without notice period or termination fees provided invoices are paid; fixed contracts roll onto SmartFlex at end of term if no new prices are agreed. Free smart meter installation typically 4-8 weeks after switching. Complaints procedure maximum eight weeks, then Energy Ombudsman (0330 440 1624). Old dual-energy.co.uk email addresses and the Worthing 'Premium House' address on the legacy page are no longer listed by the supplier.

Sources

Checked September 2026