SmartestEnergy offers one of the broader business energy product ranges in the UK, covering fixed-price contracts, renewable electricity, zero-standing-charge tariffs, variable products, advance payment and sophisticated flexible purchasing arrangements for larger organisations.
The supplier operates two related propositions. SmartestEnergy Business primarily serves small and medium-sized companies, while SmartestEnergy Limited supplies larger commercial and industrial customers. This means its services can accommodate businesses ranging from small shops and hospitality venues to large multi-site property portfolios and energy-intensive organisations.
Our review finds that SmartestEnergy is particularly competitive on product choice, renewable electricity credentials and smart-meter services. Its main limitations are the lack of publicly available fixed-contract prices, potentially significant administration charges and mixed customer experiences when billing problems arise.
SmartestEnergy at a glance
| Feature | SmartestEnergy details |
|---|---|
| Small business supplier | SmartestEnergy Business Limited |
| Large business supplier | SmartestEnergy Limited |
| Electricity supplied | Yes |
| Gas supplied | Yes |
| Fixed contracts | Generally available for one to five years |
| Variable tariff | SmartFlex |
| Renewable electricity | SmartFix Renewable and several large-business options |
| Zero standing charge | Available through SmartFix Zero |
| Advance payment | Available for qualifying electricity customers |
| Smart meters | Free installation, subject to eligibility and site conditions |
| Online account | SmartWeb for smaller businesses |
| Large-business tools | eBilling, SourceProfile and flexible purchasing platforms |
| Parent company | Marubeni Corporation |
| Small business threshold | Generally below 300,000 kWh or £50,000 annual expenditure |
| Customer service hours | 8.30am to 5pm, Monday to Friday |
| Trustpilot rating | 4.1 out of 5 from approximately 5,700 reviews |
SmartestEnergy Business Limited is an active UK company incorporated in January 2008. It originally traded as Dual Energy before being acquired by SmartestEnergy in December 2019 and rebranded as SmartestEnergy Business in 2020. The wider group is wholly owned by Japanese trading and investment company Marubeni Corporation.
EnergyCosts.co.uk rating
| Review category | Rating |
|---|---|
| Tariff choice | 4.7 out of 5 |
| Renewable electricity | 4.7 out of 5 |
| Smart meters and digital tools | 4.4 out of 5 |
| Pricing transparency | 3.5 out of 5 |
| Customer service | 4.0 out of 5 |
| Suitability for larger businesses | 4.6 out of 5 |
| Overall rating | 4.3 out of 5 |
SmartestEnergy scores particularly well for the number of different purchasing structures available. It is unusual to find one supplier offering conventional fixed contracts, renewable tariffs, zero-standing-charge pricing, advance payment, variable supply, annually reviewed tariffs and complex wholesale purchasing arrangements.
Pricing transparency is weaker because businesses must normally request a personalised quotation for fixed contracts. There is also some inconsistency across SmartestEnergy’s published information: its principal product pages advertise contracts of up to five years, while one switching FAQ refers to prices fixed for up to four years. Businesses should therefore make sure the precise duration is confirmed in the final quotation and contract documentation.
Who can use SmartestEnergy?
SmartestEnergy generally directs businesses consuming less than 300,000 kWh a year or spending less than £50,000 towards SmartestEnergy Business. Larger commercial and industrial customers are directed to SmartestEnergy Limited.
There is some overlap. SmartestEnergy Business also provides a medium-to-large business service for organisations using more than 100,000 kWh, spending over £30,000, operating half-hourly meters or managing multi-site portfolios. These customers can receive bespoke pricing and dedicated account management without necessarily moving to the full large-corporate proposition.
This gives SmartestEnergy a relatively smooth progression between customer sizes:
| Business type | Likely SmartestEnergy service |
|---|---|
| Small shop, office or salon | SmartestEnergy Business |
| Restaurant or seasonal venue | SmartestEnergy Business, potentially SmartFix Zero |
| Low-consumption premises | Low User product |
| Medium-sized factory or multi-site company | Medium-large business service |
| Large commercial property portfolio | SmartestEnergy Limited |
| Energy-intensive organisation | Fixed or flexible C&I contract |
| Company seeking a direct renewable agreement | Specific Renewable Supply or corporate PPA |
SmartestEnergy business electricity tariffs
SmartestEnergy Business currently promotes four principal named electricity products: SmartFix Zero, SmartFix Renewable, SmartFix Standard and SmartTracker. It also operates SmartFlex, Low User, SmartPay and deemed arrangements for customers in particular circumstances.
SmartFix Zero
SmartFix Zero is a fixed-price, zero-standing-charge electricity tariff. Instead of paying a daily fixed charge, the customer pays only through the electricity unit rate.
The product includes:
- No daily standing charge
- Fixed unit prices for one to five years
- Electricity backed by renewable generation
- Fixed Budget Plan or variable Direct Debit payments
- SmartWeb account access
- Free smart-meter installation, subject to eligibility
- Half-hourly consumption monitoring
SmartestEnergy identifies hospitality, seasonal and temporary businesses as particularly suitable customers. A business that closes for part of the year may benefit because it does not continue accumulating a daily standing charge while consuming little or no electricity.
However, zero standing charge does not automatically mean zero fixed cost. Suppliers commonly recover the missing standing charge through a higher unit price. The quote must therefore be compared using the business’s expected annual consumption.
For example, suppose a conventional tariff has a £1 daily standing charge and the zero-standing-charge tariff has a higher unit price:
| Annual electricity use | Maximum unit-rate premium before £1-a-day saving is lost |
|---|---|
| 5,000 kWh | 7.30p per kWh |
| 10,000 kWh | 3.65p per kWh |
| 25,000 kWh | 1.46p per kWh |
| 50,000 kWh | 0.73p per kWh |
A low-usage or seasonal business can tolerate a larger unit-rate premium. For a high-consumption company, even a small increase in the unit rate can outweigh the standing-charge saving.
SmartFix Renewable
SmartFix Renewable provides fixed-price electricity matched with UK-recognised renewable certificates. SmartestEnergy says the electricity is sourced from technologies including wind, hydro and solar, with its certificate-allocation process independently verified by the Carbon Trust.
Customers can receive:
- Prices fixed for one to five years
- Electricity matched with Renewable Energy Guarantees of Origin
- An annual renewable energy label
- Personalised materials for communicating renewable credentials
- Fixed or variable Direct Debit payments
- Smart-meter and consumption-monitoring services
It is designed for businesses seeking to reduce reported market-based Scope 2 emissions or demonstrate progress towards environmental targets.
SmartFix Standard
SmartFix Standard is SmartestEnergy’s conventional fixed-price product. It is intended for businesses that prioritise price certainty but do not require the renewable certificate package included with SmartFix Renewable.
Its principal features are:
- A fixed price for the agreed contract period
- Contract options advertised for up to five years
- Fixed Budget Plan or variable Direct Debit payments
- SmartWeb access
- Free smart-meter installation
- Half-hourly usage information where available
This is the most straightforward option for companies with predictable consumption and a preference for setting their energy budget in advance.
SmartTracker
SmartTracker sits between a conventional long-term fix and a fully variable tariff. Prices are fixed for 12 months, after which SmartestEnergy reviews the market and issues prices for the next annual period.
The supplier also advertises a price-match feature during the annual price review if the customer finds a cheaper qualifying offer elsewhere.
This may appeal to businesses that want short-term price certainty while retaining some exposure to future market reductions. Its disadvantage is that future annual prices are unknown when the arrangement begins.
Businesses should obtain the full price-match conditions before signing, including:
- Which competing quotations qualify
- Whether the quote must have identical payment terms
- Whether broker commission must be included
- The period allowed for submitting an alternative quote
- What happens if SmartestEnergy does not match it
SmartestEnergy variable and specialist tariffs
SmartFlex
SmartFlex is a variable tariff without a long-term fixed commitment. Customers can move supplier without termination charges or a notice period, provided outstanding invoices have been paid.
Existing customers normally move onto SmartFlex if they reach the end of a fixed contract without agreeing new contract prices. Rates can subsequently change, although SmartestEnergy states that it will give advance notice.
SmartFlex offers valuable flexibility, but it should not be treated as a permanent default. Its published standing charges are substantial, and its prices can change with market conditions.
Low User
The Low User electricity product is intended for businesses consuming typically less than 5,000 kWh a year. It is a variable tariff because very small accounts may not qualify for SmartestEnergy’s discounted fixed-contract rates.
Although its published unit rate is lower than the standard SmartFlex rate, the daily standing charge remains significant. A business using only a few thousand kilowatt-hours should compare the complete annual cost rather than focusing on the unit rate.
SmartPay and Advance Pay
SmartPay is an advance-payment service that allows qualifying customers to add credit online, by telephone or through automated payments. SmartestEnergy presents it as suitable for companies with unpredictable cash flow or those needing to remain on supply while repaying an outstanding balance.
Electricity customers can receive credit alerts by text message or email.
Two published pricing levels are shown: Advance Pay Standard and Advance Pay Reward. Eligibility for the lower Reward prices should be confirmed directly with SmartestEnergy.
Deemed tariff
A deemed tariff may apply when a business moves into premises already supplied by SmartestEnergy but has not agreed a contract. It can also apply in certain payment-related circumstances, including cancellation of a Direct Debit or failure to maintain an agreed payment arrangement.
Deemed rates are normally considerably more expensive than negotiated contract rates. New occupiers should contact the supplier immediately, provide opening meter readings and arrange a contract or switch.
Current SmartestEnergy published prices
SmartestEnergy does not publish universal fixed-contract prices because quotations depend on factors such as the meter, postcode, consumption, credit assessment, contract start date, payment method and contract duration.
It does, however, publish prices for its variable, deemed, low-user and advance-payment products. The following rates exclude VAT and the Climate Change Levy.
Non-half-hourly electricity prices
| Tariff | Effective date | Profile class | Standing charge | Unit rate |
|---|---|---|---|---|
| SmartFlex | April 2026 | 1–4 | 350p per day | 34.00p per kWh |
| SmartFlex | April 2026 | 5–8 | 450p per day | 34.00p per kWh |
| Deemed | June 2026 | 1–4 | 400p per day | 43.00p per kWh |
| Deemed | June 2026 | 5–8 | 500p per day | 43.00p per kWh |
| Low User | April 2026 | 1–4 | 350p per day | 22.50p per kWh |
| Low User | April 2026 | 00 and 5–8 | 430p per day | 22.50p per kWh |
| Advance Pay Standard | April 2026 | 1–8 | 600p per day | 39.00p per kWh |
| Advance Pay Reward | April 2026 | 1–4 | 300p per day | 25.00p per kWh |
| Advance Pay Reward | April 2026 | 00 and 5–8 | 450p per day | 25.00p per kWh |
Half-hourly electricity prices are more complex. SmartestEnergy publishes different standing charges according to voltage level, charging band and profile class. SmartFlex half-hourly unit prices range from 22p to 25p per kWh in the current publication, while deemed half-hourly rates range from 39p to 49p per kWh. Standing charges can be much higher for large-capacity connections.
Business gas prices
| Tariff | Effective date | Standing charge | Unit rate |
|---|---|---|---|
| SmartFlex gas | April 2026 | 500p per day | 3.90p per kWh |
| Deemed gas | June 2026 | 600p per day | 13.00p per kWh |
The difference between SmartFlex and deemed gas is particularly large. Businesses occupying a new site should therefore avoid remaining on the deemed tariff unnecessarily.
Example annual SmartestEnergy costs
The examples below use the published variable rates and assume consumption remains constant throughout the year. They exclude VAT, the Climate Change Levy, any additional capacity charges and ancillary fees.
Electricity example
A profile-class 1–4 business using 25,000 kWh annually would have the following estimated costs:
| Tariff | Energy charge | Annual standing charge | Estimated annual total |
|---|---|---|---|
| SmartFlex | £8,500.00 | £1,277.50 | £9,777.50 |
| Deemed | £10,750.00 | £1,460.00 | £12,210.00 |
The SmartFlex tariff would cost approximately £2,432.50 less, equivalent to a reduction of about 19.9% compared with the deemed tariff.
Gas example
A business using 50,000 kWh of gas annually would have the following estimated costs:
| Tariff | Energy charge | Annual standing charge | Estimated annual total |
|---|---|---|---|
| SmartFlex gas | £1,950.00 | £1,825.00 | £3,775.00 |
| Deemed gas | £6,500.00 | £2,190.00 | £8,690.00 |
In this example, moving from deemed gas to SmartFlex would reduce the estimated annual charge by £4,915, or approximately 56.6%. A negotiated fixed tariff could differ from both amounts.
Large-business SmartestEnergy tariffs
Larger commercial and industrial customers can access more sophisticated purchasing arrangements through SmartestEnergy Limited.
Fixed-price contracts
Large businesses can fix the wholesale component of their electricity costs for between one and five years. Depending on the contract, non-commodity costs can also be fixed or passed through to the customer as they change.
A fully fixed structure provides greater budget certainty. A pass-through arrangement may initially appear cheaper but exposes the business to changes in network, policy and system costs.
Flexible purchasing contracts
Flexible contracts allow businesses to purchase electricity in separate tranches rather than fixing the entire requirement on one day. Purchases can be made monthly, quarterly or seasonally through SmartestEnergy’s trading team.
These contracts are most appropriate for businesses that have:
- Significant annual electricity expenditure
- An internal energy procurement team
- Support from an energy consultant
- Reliable consumption forecasts
- A formal risk-management policy
- The ability to monitor wholesale market movements
Flexible purchasing can reduce the risk of fixing all consumption at an unfavourable moment, but it does not guarantee a lower final price.
Large-business renewable options
SmartestEnergy offers several levels of renewable electricity procurement:
| Renewable option | Main feature |
|---|---|
| Standard Renewable Supply | Renewable certificates allocated for each megawatt-hour supplied |
| Natural Renewable Supply | Supply matched with natural technologies such as wind, solar, hydro and tidal |
| Specific Renewable Supply | Supply tailored by technology, generator or location |
| Traceable Renewable Supply | Half-hourly consumption matched with certificates from named generators |
| Corporate PPA | Long-term agreement linked to a renewable generation project |
The Traceable Renewable Supply product allocates REGOs at half-hourly intervals from a ring-fenced pool of named generators. SmartestEnergy says generators used for the product are less than 15 years old. The platform also allows customers to calculate and report a Carbon Free Energy score.
A corporate power purchase agreement offers the strongest connection to a particular renewable project. It can also demonstrate additionality where the contract supports the financing of new generation, although CPPAs involve longer commitments and more complicated volume and pricing risks.
How renewable is SmartestEnergy?
SmartFix Renewable is certificate-backed rather than a direct physical connection between the customer and a renewable generator. SmartestEnergy allocates UK-recognised renewable certificates against the electricity consumed, with the process independently verified by the Carbon Trust.
For April 2024 to March 2025, SmartestEnergy Business reported the following product fuel mixes:
| Product category | Published generation mix |
|---|---|
| Renewable products | 50% biomass or thermal renewable generation and 50% wind |
| Conventional products | 75% natural gas, 15% coal, 4% nuclear, 6% other and 0.3% renewable |
SmartestEnergy states that each megawatt-hour supplied through its renewable products is backed by a renewable-origin certificate.
The renewable product is therefore useful for market-based carbon reporting, but companies with stricter procurement policies may prefer Specific Renewable Supply, half-hourly Traceable Renewable Supply or a corporate PPA.
Smart meters and energy monitoring
SmartestEnergy Business offers free smart-meter installation where the existing metering arrangement and site are suitable. Installation normally takes place four to eight weeks after switching.
The supplier estimates that:
- A typical installation takes 60 to 90 minutes
- Electricity may be interrupted for approximately 15 to 30 minutes
- Around 80% of its customers use smart-meter technology
- Automated readings may take several weeks to begin after installation
Existing smart meters may be retained if they are compatible with SmartestEnergy’s metering network.
Once connected, customers can view half-hourly consumption information and create daily, weekly or monthly reports. This is useful for identifying overnight baseload, excessive heating or cooling, equipment left operating outside working hours and differences between sites.
SmartWeb online account
SmartWeb is SmartestEnergy Business’s account-management portal. Customers can use it to:
- View and download invoices
- Submit meter readings
- Monitor energy use
- Make online payments
- View account statements
- Update contact details
- Link multiple accounts and premises under one login
The multi-site feature is particularly valuable for businesses managing several branches because users do not need to register separately for each account.
Larger SmartestEnergy Limited customers use separate tools. These include eBilling for invoices and consumption data, SourceProfile for detailed meter and site analysis and trading platforms for flexible procurement customers.
Payment options
SmartestEnergy Business offers fixed and variable Direct Debit arrangements.
A fixed Budget Plan estimates the customer’s annual expenditure and divides it into 12 monthly payments. Smart-meter data is then used to monitor whether the payment remains appropriate. If SmartestEnergy changes the monthly amount, it says it will provide at least ten days’ notice.
Under variable Direct Debit, the customer pays for the energy actually billed each month, meaning payments can be higher during periods of heavier seasonal consumption.
The Budget Plan can help cash-flow forecasting, but businesses should continue checking invoices and meter data. A fixed monthly payment does not mean the underlying bill is fixed if actual consumption differs from the original estimate.
Additional SmartestEnergy charges
SmartestEnergy publishes a separate administration and service-charge schedule. The document currently linked from its product page is dated February 2025, so customers should confirm that the figures remain applicable before acting on them.
Selected published charges include:
| Charge | Published amount excluding VAT |
|---|---|
| Additional paper invoice copy | £7.50 |
| Cheque or card processing without Direct Debit | £12.50 per payment |
| BACS processing without Direct Debit | £12.50 per payment |
| Late payment fee | £44.95 |
| Failed Direct Debit or returned cheque | £35.00 |
| Cancelled Direct Debit | £39.00 |
| Arrangement to pay fee | £49.95 |
| No Direct Debit monthly surcharge | £25.00 per month |
| VAT invoice amendment | £10.00 |
| Non-cyclic meter reading | £12.00 |
| Aborted engineer visit | £150.00 |
The £25 monthly surcharge for accounts without Direct Debit is especially important. It could add £300 a year before VAT, materially changing the result of a tariff comparison.
SmartestEnergy customer service reviews
SmartestEnergy Business has a Trustpilot score of 4.1 out of 5, based on 5,727 reviews at the time checked. The published distribution was:
| Trustpilot rating | Percentage of reviews |
|---|---|
| Five stars | 71% |
| Four stars | 7% |
| Three stars | 2% |
| Two stars | Less than 1% |
| One star | 19% |
The overall result is positive, but the distribution is relatively polarised. Many positive reviewers praise individual customer-service advisers for being helpful, professional and quick to resolve straightforward queries. Recent negative reviews allege issues involving estimated consumption, unexpectedly large Direct Debits, delayed corrections, refunds and complaint handling. These are individual customer accounts rather than verified findings, but the proportion of one-star reviews should not be ignored.
Customer services can be contacted between 8.30am and 5pm from Monday to Friday. SmartestEnergy also provides a 24-hour automated meter-reading telephone service.
Complaints procedure
Customers should initially raise a complaint with SmartestEnergy’s customer-service team. The company’s formal process can take up to eight weeks and includes internal escalation.
A microbusiness or eligible small business can refer the case to the Energy Ombudsman after receiving a deadlock letter or if the complaint remains unresolved for eight weeks.
Businesses should retain:
- Copies of invoices
- Photographs of meter readings
- Smart-meter data
- Bank statements showing payments
- Emails and letters
- Dates and notes from telephone calls
- The original contract and renewal documentation
These records can be particularly important where a dispute concerns estimated readings, change-of-occupancy dates or Direct Debit collections.
Switching to SmartestEnergy
SmartestEnergy says the earliest switching time for electricity or gas is approximately five working days, subject to approval, credit checks and any objection from the existing supplier.
After acceptance, a welcome pack is normally sent by email within 48 hours. The supplier then requests an opening meter reading near the supply start date.
Before accepting a quotation, check:
- Whether prices are fully fixed or include pass-through costs
- The contract start and end dates
- The unit rate and standing charge
- Whether broker commission is included
- Payment requirements
- Renewable certificate costs
- Early termination provisions
- Renewal and rollover arrangements
- Capacity and metering charges
- Additional administration fees
SmartestEnergy advantages and disadvantages
Advantages
Broad tariff selection: SmartestEnergy offers more tariff structures than many smaller business suppliers, including zero-standing-charge, renewable, variable, tracked and advance-payment options.
Strong renewable proposition: Carbon Trust verification, renewable labels and multiple large-business procurement levels provide meaningful choices for companies with environmental reporting requirements.
Free smart meters: Eligible small-business customers can receive installation without a separate upfront charge.
Useful consumption data: Half-hourly monitoring and multi-site reporting can help businesses identify avoidable usage.
Suitable for different business sizes: The group can serve small premises, medium-sized companies and complex C&I portfolios.
Financial backing: Ownership by Marubeni provides stronger corporate backing than many independent challenger suppliers.
Disadvantages
No standard fixed prices: Businesses cannot judge SmartFix competitiveness without completing a quotation.
High published standing charges: SmartFlex and deemed tariffs can carry daily charges of several pounds, even for relatively small non-half-hourly accounts.
Additional fees: Late payment, failed Direct Debit and non-Direct-Debit charges can materially increase costs.
Mixed billing experiences: Although the overall customer rating is good, a significant minority of reviews report serious billing or account-resolution problems.
Product-page inconsistencies: Published information does not always agree on whether the maximum fixed term is four or five years.
Zero standing charge requires careful calculation: SmartFix Zero may not be cheaper for businesses with high annual consumption.
Is SmartestEnergy a good business energy supplier?
SmartestEnergy is a strong option for businesses that want more than a basic fixed electricity contract. Its renewable products, free smart-meter programme, detailed consumption monitoring and range of payment structures make it especially attractive to environmentally focused small businesses and companies seeking better control over their usage.
SmartFix Zero is potentially valuable for seasonal and low-utilisation premises, while SmartFix Renewable offers credible certificate-backed renewable electricity. Larger organisations also benefit from access to flexible procurement, half-hourly renewable matching and corporate PPAs.
The supplier is less compelling for businesses that want completely transparent online prices without speaking to a sales adviser. Customers must also pay close attention to ancillary fees, Direct Debit requirements, pass-through charges and post-contract SmartFlex rates.
Overall, SmartestEnergy deserves a place on a business energy quotation shortlist. However, its offer should be compared using the total annual cost rather than the headline unit rate, and every fixed, renewable and zero-standing-charge quotation should be assessed against at least two competing suppliers.
FAQ
Yes. SmartestEnergy Business offers both business gas and electricity. Its widest named tariff range applies to electricity, although fixed and variable gas products are also available. Larger commercial customers can obtain more complex electricity purchasing arrangements through SmartestEnergy Limited.
SmartFix products provide fixed pricing for an agreed period, generally advertised for between one and five years. SmartFlex, Low User, deemed and Advance Pay tariffs are variable. Large-business contracts may fix the wholesale element while allowing some network or policy costs to pass through.
SmartFix Renewable electricity is matched with UK-recognised renewable certificates through a process independently verified by the Carbon Trust. Larger customers can choose more detailed options, including named-source supply, half-hourly matching and corporate power purchase agreements.
SmartestEnergy Business offers free smart-meter installation where the site and existing metering arrangement are suitable. Installation is normally arranged within four to eight weeks and may require a short interruption to the electricity supply.
SmartestEnergy states that SmartFlex customers can switch supplier without a termination fee or notice period, provided all outstanding invoices have been paid. Customers on fixed contracts may have different termination obligations and should check their contract.
Yes. SmartestEnergy Business is primarily aimed at smaller and medium-sized organisations. Its range includes fixed, renewable, zero-standing-charge, low-user, variable and advance-payment products, although availability and prices depend on the business’s consumption, meter and credit assessment.
