The Smart Export Guarantee (SEG) is the regulatory scheme that requires UK electricity suppliers above 150,000 customers to pay solar PV generators for the surplus electricity they export to the grid. It replaced the Feed-in Tariff for new installs from 1 April 2020, runs in parallel with the older FiT scheme for legacy systems, and operates as a market-rate product — each supplier sets their own SEG tariff and customers can switch between suppliers separately from their import contract. For commercial customers in 2026, SEG income runs from £3,300 per year on a typical 100 kW office system through to £20,000+ on a 500 kW warehouse — material money on a 25-year asset, and the supplier choice can swing total income by 30 to 40 percent over the life of the system. This page lays out every commercial SEG tariff available in 2026, eligibility, the application process, switching mechanics, and the strategies that maximise export income.
How the SEG scheme works
SEG is mandated under the Electricity Supplier Obligation (Smart Export Guarantee) Order 2019 and is regulated by Ofgem. The legal duty falls on electricity suppliers above 150,000 domestic and non-domestic customers to offer at least one SEG tariff to eligible generators. The minimum rate must be above zero — but Ofgem deliberately did not set a floor or ceiling, on the principle that competitive supplier pricing would deliver fair rates. The result has been a wide spread, from sub-5p tariffs at the bottom end through to 16.5p at the top in 2026.
The mechanism: you generate, your meter records the half-hourly export to the grid, your SEG supplier reads that meter reading (typically monthly), and pays you per kWh exported at the agreed tariff. Most suppliers credit the export income against the import bill if you are also an import customer; SEG-only customers (where the import supplier is different) receive a quarterly bank transfer.
Commercial vs domestic SEG
The headline rules are the same for both. Where commercial differs:
Supplier scope is narrower. Ofgem requires only suppliers above 150,000 customers to offer SEG. Several niche commercial-focused suppliers (Crown Gas and Power, Yu Energy, Pozitive Energy, Total Gas and Power) do not have to participate, and most do not. The practical commercial SEG market is the major retail suppliers: Octopus, EDF, British Gas, OVO, E.ON Next, Scottish Power, Shell Energy, So Energy, Tesla, Utilita.
Tariff structures are simpler. Most suppliers offer one commercial SEG tariff and one domestic — some have unified rates, others split. Commercial typically gets the simpler fixed rate; complex options like time-of-use export tariffs (Outgoing Agile) are available to commercial customers but uptake is lower than domestic.
Application paperwork is heavier. Commercial applications need MCS certificate, G98/G99 paperwork, business identity verification, and (where landlord/tenant relationships exist) clarity on who the SEG-eligible party is.
2026 commercial SEG tariff comparison
| Supplier | Tariff name | Rate (p/kWh) | Term | Notes |
|---|---|---|---|---|
| E.ON Next | Export Exclusive | 16.5p | 12 months | Premium tier customers only — restrictive eligibility |
| Octopus Energy | Outgoing Octopus | 15.0p | 12 months | Highest broadly-available rate; Octopus import customer |
| Scottish Power | SmartGen | 12.0p | 12 months | Strong rate for Scotland-based commercial sites |
| Octopus Energy | Outgoing Agile | variable, avg 11p | day-ahead | Tracks wholesale; can spike to 30p+ on tight days |
| Tesla | Tesla Solar Export | 9.0p | 12 months | Tesla Powerwall customers only — battery-tied |
| British Gas | Export and Earn | 6.4p | 12 months | Mid-tier; works with any import supplier |
| EDF Energy | Export+ Variable | 5.6p | 12 months | Standard tier |
| OVO Energy | Solar Export | 4.0p | 12 months | Lower tier |
| Shell Energy | Energy Export | 5.0p | 12 months | Closing to new customers Q3 2026 |
| Utilita | SEG Standard | 3.0p | 12 months | Lowest in the table — avoid for commercial |
The headline gap between Octopus Outgoing at 15p and Utilita at 3p is a 5x difference — across a 100 kW office system exporting 30,000 kWh per year, the income difference is £4,500 versus £900, every year, for the life of the system. SEG choice is not a small-print decision.
Eligibility — who can apply
Five tests, all of which must be met:
MCS certification. The installation must be MCS-certified by an MCS-listed installer using MCS-listed panels and inverter. Self-installs and unlisted equipment are not eligible. The MCS scheme covers solar PV, wind turbines, micro-CHP, hydroelectric, and AD plants — all are SEG-eligible.
System under 5 MW. The vast majority of commercial systems are under 5 MW (most commercial rooftops top out at 500 kW; only ground-mount solar farms approach 5 MW). Above 5 MW you are in the wholesale market via PPA or in-trade rather than SEG.
G98 or G99 commissioned. The grid connection must be approved by the DNO under Engineering Recommendation G98 (sub-3.68 kW per phase, applicable mostly to small commercial) or G99 (above that, the standard for commercial). Commissioning paperwork from the DNO is the proof — see /g98-application/ and /g99-application/.
Half-hourly export metering. A smart meter or export meter capable of half-hourly readings is required. Most commercial sites have half-hourly meters as standard already; if not, the installer specifies a separate Carlo Gavazzi or similar export meter at install.
Single MPAN per generator. The export MPAN must match the generator location. Multi-site businesses cannot pool exports across MPANs — each site has its own SEG arrangement.
Application process
Choose your SEG supplier, gather paperwork, submit. Three to eight weeks from submission to first export payment is typical. Steps:
Step 1: Choose the supplier. Compare 2026 rates from the table above, factor in any conditions (Octopus needs you to be an Octopus import customer for Outgoing standard; E.ON Export Exclusive needs the premium tier import contract; Tesla Solar Export needs a Tesla Powerwall installed). For most commercial sites without those constraints, Octopus Outgoing or Scottish Power SmartGen are the practical top choices.
Step 2: Submit the application. Most suppliers have an online portal — you upload the MCS certificate, G98 or G99 paperwork, copy of recent electricity bill showing the import MPAN, and any business identity proof requested. The supplier acknowledges within 5 working days.
Step 3: Meter validation. The supplier checks the export meter MPAN is registered and reading. If the meter is not yet capable of half-hourly export reading, they arrange a meter exchange (typically free, 4 to 6 week lead time).
Step 4: Tariff activation. Once meter readings come in, the tariff is activated and back-dated to the application date in most cases. First payment lands 4 to 8 weeks after activation.
Switching SEG suppliers
You can switch SEG suppliers separately from your import supplier. Two practical scenarios:
You are unhappy with your current rate. Apply to a new SEG supplier, give 28 days notice to the existing supplier (or follow their published switch process), and the new tariff activates after the notice period. Most commercial customers do this every 12 to 18 months as supplier rates drift.
Your import contract changes but you want to keep the SEG supplier. Common scenario when a business switches import supplier mid-year for a better fixed rate. The SEG arrangement continues unaffected — the export meter readings still flow to your existing SEG supplier, the existing supplier still pays you. SEG and import contracts are decoupled.
One technical note: some suppliers offer SEG only to their own import customers (Octopus's standard Outgoing tariff has historically required this; their SEG-only product gives access without the import tie). Check the small print before assuming you can sign up as a SEG-only customer.
Maximising SEG income — three strategies
Self-consume first, export second. The mathematical reality of UK commercial PV is that a kWh self-consumed saves you 21 to 28p (the import retail rate), while a kWh exported earns you 4 to 16p (the SEG rate). Always more valuable to self-consume. Right-size the system to your daytime load, route variable loads (EV chargers, water heating) onto solar generation, and design battery storage to plug evening shoulder demand. After self-consumption is optimised, export the leftover.
Battery time-shift onto Outgoing Agile. Pair solar with battery storage on Octopus Outgoing Agile and use scheduling software (Predbat, PowerDog, GivEnergy) to discharge the battery into the half-hours with the highest day-ahead export rates. Common 2025-2026 pattern: midday-charge the battery from PV, hold the charge through afternoon, discharge into the 17:00-19:00 wholesale peak when prices typically run 20 to 30p per kWh on Agile. Real-world uplift versus fixed Outgoing: 20 to 35 percent more annual export income. Worth the operational complexity for sites above 50 kW.
Switch annually. Set a calendar reminder for 30 days before your SEG tariff anniversary and check the market. Rates drift, premium tiers open and close, and the savings from a one-hour annual switch can be £500 to £3,000 per year on a typical commercial site.
Worked income forecasts
100 kW office, average self-consumption 75 percent, on Octopus Outgoing at 15p. Annual generation ~95,000 kWh, self-consumption ~71,250 kWh (saves £14,250 to £19,950 against import), exported ~23,750 kWh × 15p = £3,563. Total annual benefit: £18,000 to £23,500.
250 kW warehouse, self-consumption 60 percent, on British Gas Export and Earn at 6.4p. Annual generation ~240,000 kWh, self-consumption ~144,000 kWh (saves £30,240 to £40,320), exported ~96,000 kWh × 6.4p = £6,144. Total annual benefit: £36,400 to £46,500. Switch this site to Octopus Outgoing at 15p and SEG income jumps to £14,400 — additional £8,250 per year for free.
500 kW farm shed, self-consumption 35 percent (low daytime load), on Scottish Power SmartGen at 12p. Annual generation ~475,000 kWh, self-consumption ~166,250 kWh (saves £34,900 to £46,550), exported ~308,750 kWh × 12p = £37,050. Total annual benefit: £72,000 to £83,600. The export income is dominant here because the rural farm shed has low daytime load — the SEG choice is the decisive driver.
Authority resources
Ofgem SEG scheme overview and rules: Ofgem — Smart Export Guarantee. MCS-listed installer database: MCS Certified. Energy Networks Association G98/G99: Energy Networks Association. Citizens Advice supplier customer count list (the 150,000-customer threshold): Citizens Advice.
Related decision pages
Grants and funding covers other revenue streams alongside SEG. PPA is the alternative to SEG when you want a third party to own the asset. Battery storage for time-shift strategies. Commercial solar PV for the broader business case. G98 application and G99 application for the grid connection prerequisite. Capital allowances for the tax treatment. Cost guide for what an installation costs. Are commercial solar panels worth it for the underlying ROI question. TNUoS and DUoS charges for the import-side tariff structure that makes self-consumption valuable.
SEG tariffs — common questions
Can I be on a different supplier for SEG export vs grid import?
Yes. Ofgem rules under the Smart Export Guarantee scheme do not require you to be the import customer of the SEG supplier. You can buy your electricity from EDF on a fixed contract while signing up to Octopus Outgoing for SEG export — they are completely separate contractual arrangements. Most commercial customers benefit from this split because import procurement decisions (price, term, green certification) are different from export decisions (highest p/kWh available now). The administrative trade-off is two relationships to manage and two sets of paperwork at change of tenancy or change of supplier.
What is the best SEG tariff for UK businesses in 2026?
On a flat-rate basis, E.ON Next Export Exclusive at 16.5p/kWh and Octopus Outgoing at 15p/kWh lead the table. E.ON requires you to be on a premium import tariff with them, so true accessibility is narrower; Octopus Outgoing requires Octopus to be your import supplier on the standard pathway, but a separate Octopus SEG-only sign-up is available with a slight rate adjustment. For sites with battery storage and the operational appetite to time-shift export, Octopus Outgoing Agile (variable, day-ahead pricing) regularly beats fixed tariffs, particularly on summer evenings when wholesale prices spike. For straightforward office and warehouse sites without batteries, the simplest highest-fixed-rate available is the right answer.
How is commercial SEG eligibility different from domestic?
The headline rules are the same — MCS certification mandatory, system commissioned under G98 or G99, system below 5 MW capacity, and a smart meter or export meter installed for half-hourly export reading. The practical difference is supplier scope: Ofgem requires only suppliers with above 150,000 customers to offer SEG. Smaller suppliers like Bulb (now part of Octopus) and So Energy do not have to participate, and many smaller commercial-focused suppliers (Crown, Yu Energy, Pozitive Energy) do not. For a commercial customer, the practical SEG market is Octopus, EDF, British Gas, OVO, E.ON Next, Scottish Power, Shell Energy, So Energy, Tesla, and Utilita. Switch rates between these suppliers are unrestricted.
What documents do I need to apply for SEG?
Four documents typically: MCS certificate from your installer (proves panel and inverter are MCS-listed and the install was MCS-certified), G98 or G99 commissioning paperwork from the DNO (proves the grid connection is approved), a copy of your DNO connection notification with export meter MPAN, and a recent electricity bill showing the import meter MPAN at the same address. Some suppliers also ask for proof of business identity (companies house registration extract or utility bill in the business name) particularly when the SEG customer differs from the import customer. Application processing is usually 4 to 8 weeks from submission to first export payment.
Should I export everything or maximise self-consumption first?
Always self-consume first. Self-consumed kWh save you the full retail import price (currently 21 to 28p per kWh on UK commercial standard tariffs), which is materially higher than the 5 to 16p available on SEG export. Battery storage tilts this further — battery cycles let you shift midday surplus to evening loads, replacing peak-rate import with off-peak self-consumption. Only after self-consumption is maxed out and battery is full should export occur, at which point the SEG tariff becomes the marginal rate. The mathematical answer for most UK commercial sites in 2026 is: target 65 to 80 percent self-consumption, export the remaining 20 to 35 percent at the highest SEG rate available.
How do I time-shift export for higher SEG income?
Pair solar PV with battery storage and a tariff like Octopus Outgoing Agile that prices export based on day-ahead wholesale rates. Octopus pushes the next-day half-hourly rates to the API at 4pm; software like Predbat or PowerDog integrates with the inverter to schedule battery export into the highest-rate half-hours of the next day, typically 17:00 to 19:00 in winter. Real-world uplift versus fixed-rate Octopus Outgoing: typically 20 to 35 percent more annual export income, requires a battery sized to at least 50 percent of daily generation to be worthwhile. Best suited to commercial sites with operational engineering capacity to set this up — see /services/battery-storage/.
Is the SEG income I receive taxable for my business?
Yes. SEG income paid to a UK business is taxable as trading or rental income depending on the contractual arrangement — for most commercial sites it falls within trading receipts and is included in the corporation tax return alongside other income. The same accounting treatment applies as for any other commercial revenue stream. Capital allowances on the solar PV asset are claimed separately and provide a 100 percent first-year deduction under the Annual Investment Allowance — see /capital-allowances-solar-panels/. Talk to your accountant; the typical net-of-tax SEG income for a Ltd company is roughly 75 percent of gross.