Every business owner knows the sinking feeling of opening an electricity bill that is higher than expected. What fewer people realise is that two businesses using exactly the same amount of power in a month can end up with very different bills, purely because of when that power was used.
Electricity is not priced like a flat monthly subscription. Depending on your tariff, meter and supplier, running ovens, machinery or air conditioning at 5 pm on a Tuesday can cost far more than running the same equipment at 2 am. That gap between peak and off-peak business electricity is one of the simplest, most overlooked ways for a UK business to cut costs, without buying a single piece of new kit or renegotiating a contract.
In this guide, we break down what peak and off-peak actually mean for commercial electricity, which high-usage equipment is genuinely worth shifting, and how comparing business electricity suppliers through a service like SwitchUrEnergy can help you find a tariff that rewards the change.
In short UK business electricity is typically most expensive between 4 pm and 7 pm on weekdays (the “peak” or “red” period) and cheapest overnight and at weekends (the “off-peak” or “green” period). Shifting flexible, high-usage equipment, such as production runs, EV charging, laundry or water heating, into off-peak hours can noticeably cut your bill, especially on a half-hourly meter or time-of-use tariff. Always-on loads like server rooms and cold storage should stay put. The goal is not to eliminate peak usage entirely, just to stop paying peak prices for the usage you can control. |
What Do Peak and Off-Peak Actually Mean for Business Electricity Suppliers?
Peak and off-peak are simply shorthand for how busy the national grid is at any given moment. Electricity demand across the UK rises and falls in a fairly predictable daily rhythm. It climbs through the morning as businesses open, eases slightly around lunch, then climbs sharply in the late afternoon as offices, shops, homes and industry are all drawing power at once. It falls away again overnight, once most premises are closed and households have gone to bed.
Because generating and moving electricity at short notice during those busy periods costs more, suppliers and network operators pass some of that cost on through higher prices at peak times, and reward off-peak usage with a cheaper rate.
Peak Hours: When the Grid, and Your Bill, Feel the Strain
For most UK businesses, peak hours fall on weekdays between roughly 4 pm and 7 pm. This lines up with the “red band” used in Distribution Use of System (DUoS) charging, the network cost that many half-hourly metered businesses pay alongside their unit rate. Electricity used in this window is priced to reflect how much strain the system is under, and it shows up clearly on a bill.
Off-Peak Hours: The Quiet Window Worth Using
Off-peak hours generally run overnight, from around midnight to 7 am, with demand staying low across most of the weekend too. This is the “green band” in DUoS terms, and it is usually the cheapest window on a time-of-use business electricity tariff. Traditional Economy 7 style contracts have offered a version of this for decades, but modern time-of-use and smart tariffs now split the day into more precise bands.
Between the two sits a “shoulder” or “amber” period, covering most of the regular working day. It costs more than off-peak, but nowhere near as much as peak, as the table below shows.
Band | Typical Hours | DUoS Colour | Indicative Rate* | Best For |
|---|---|---|---|---|
Off-Peak | Midnight to 7 am, plus most weekends | Green | 15p to 20p/kWh | Overnight production, EV charging, laundry |
Shoulder | 7 am to 4 pm and 7 pm to midnight (weekdays) | Amber | 20p to 26p/kWh | Normal office and trading hours |
Peak | 4 pm to 7 pm (weekdays) | Red | 28p to 38p+/kWh | Avoid running flexible equipment here |
*Illustrative ranges based on UK market rates in 2026. Actual rates depend on your supplier, region, meter type and contract.
Figure 1: A typical UK business weekday, split into off-peak, shoulder and peak bands.
Why the Time You Use Electricity Matters As Much As How Much You Use
For years, businesses have focused almost entirely on cutting total consumption: switching off lights, improving insulation, buying more efficient equipment. All of that still matters. But on a modern tariff, when you use electricity can move the needle on your bill nearly as much as how much you use.
DUoS Charges and the Red, Amber, Green System
If your business has a half-hourly meter, typically required once maximum demand passes 100kVA, part of your bill includes DUoS charges set by your regional Distribution Network Operator. These are split into red, amber and green bands, and the gap between them is not small. Using power in the red band can cost several times more than the same unit of electricity used in the green band, purely because of the time on the clock. Businesses that shift even a portion of their load out of the red band tend to see it reflected directly in their next invoice.
There is also TNUoS, the transmission-level charge that historically rewarded large sites for avoiding the handful of “Triad” peak evenings each winter. Ofgem's charging reforms have moved much of this towards a more fixed, capacity-based charge in recent years, but the underlying principle has not changed: electricity used at the busiest times costs the system more, and that cost eventually lands somewhere on a bill.
Figure 2: Indicative business electricity unit rates by time band. Ranges are illustrative only.
Wholesale Prices, Smart Tariffs and Octopus Electricity
Away from network charges, the wholesale price of electricity itself also swings throughout the day, and some suppliers now pass that variation straight through to business customers. Octopus Energy for Business, for example, builds tariffs specifically around this idea. Its Agile-style business tariff prices electricity in 30-minute blocks tied to the wholesale market, while its Shape Shifters range uses simpler day, night and peak bands. Octopus has said that businesses on its Shape Shifters Agile tariff can save more than 25% by shifting usage away from the 4 pm to 7 pm peak, and that some businesses on its Trio tariff have moved almost all of their peak-time usage into cheaper hours.
Octopus electricity tariffs are not the only option. A growing number of established business electricity suppliers now offer some form of time-of-use or multi-rate pricing, but Octopus is a useful illustration of how directly a supplier's pricing structure can reward, or penalise, the timing choices your business makes.
Quick tip: if your business runs a constant, predictable load, such as a server room or cold store, a flat fixed tariff is almost always the safer choice. Save time-of-use tariffs for the equipment that can genuinely move. |
Which High-Usage Equipment Should You Move Off-Peak?
Not every piece of equipment can simply be switched to run at 2 am, and trying to force that will usually cause more problems than it solves. The businesses that save the most tend to start by sorting their equipment into what can realistically move, and what genuinely cannot.
Equipment | Can It Shift? | Practical Tip |
|---|---|---|
HVAC (heating and cooling) | Partly | Pre-heat or pre-cool just before peak starts, then ease off during the peak window itself. |
Production machinery | Often | Move a shift or batch run outside 4 pm to 7 pm where staffing allows. |
EV and forklift charging | Yes | Charge overnight on a timer or smart charger rather than plugging in after work. |
Compressors, pumps, motors | Often | Fit variable speed drives and schedule non-critical cycles for off-peak hours. |
Catering equipment (ovens, fryers) | Limited | Batch-prep outside service hours where food safety and freshness allow. |
Laundry equipment | Yes | Run wash and dry cycles overnight or first thing before the shoulder period. |
Server rooms and cold storage | No | Leave running continuously; focus on efficiency and maintenance, not timing. |
Water heating (immersion, catering) | Yes | Fit a timer so tanks heat overnight rather than during the afternoon rush. |
Equipment You Can Usually Shift
Anything with a “when” rather than an “always” requirement is worth a second look: EV charging, batch production, laundry, water heating and non-urgent machine cycles. None of these need to happen at 5 pm specifically, only before the next working day begins. A timer, a smart plug or a small change to a shift pattern is often all it takes.
Equipment That Should Stay Where It Is
Anything that keeps people, stock or data safe should not be shifted purely to chase a cheaper rate. Server rooms, medical or food storage refrigeration, and safety-critical systems need to run continuously, regardless of the time band. For this equipment, the better lever is efficiency, through maintenance, insulation or better-specified units, rather than timing.
A Worked Example: What Shifting Off-Peak Could Actually Save
Numbers make this easier to picture. Take a small light engineering firm using around 40,000 kWh of electricity a year, roughly 15% of which (about 6,000 kWh) currently falls inside the 4 pm to 7 pm peak window, because of a late shift running machinery.
Worked example 6,000 kWh used at a peak rate of around 34p/kWh costs roughly £2,040 a year. The same 6,000 kWh shifted to an off-peak rate of around 17p/kWh costs roughly £1,020 a year. Potential saving: around £1,020 a year, simply from changing when that machinery runs, not how much it uses. |
That is before factoring in any DUoS savings on a half-hourly meter, or the discount available on some time-of-use business electricity tariffs. Scale that up across a warehouse, a production site or a multi-site retailer, and the numbers start to matter a great deal more.
How to Actually Shift Your Business's Energy Use
Start With Your Meter and Tariff
You cannot benefit from off-peak pricing on a standard single-rate tariff, however disciplined your team is about switching things off. Check whether your business has a half-hourly meter (common above 100kVA maximum demand) or a smart meter capable of recording time-of-use data, and ask whether your current tariff reflects peak and off-peak pricing at all. If it does not, that is worth raising the next time you compare business electricity suppliers.
Build a Simple Load-Shifting Schedule
Walk through a typical day and note what is running between 4 pm and 7 pm. For each item, ask whether it needs to run at that exact time, or simply needs to be finished by the start of the next working day. A spreadsheet is enough to start. Set timers, smart plugs or building management system rules to automate the shift, so it does not rely on someone remembering.
Look Into the Demand Flexibility Service
Some businesses can go further and get paid for shifting demand. The Demand Flexibility Service, run by the National Energy System Operator (NESO, formerly National Grid ESO), now operates year-round, and changes introduced in 2026 have opened it up to a wider range of businesses through participating suppliers and flexibility providers. It is worth asking your supplier whether your business qualifies.
Review Your Contract Before It Renews
A time-of-use tariff is only worth having if the underlying rates are competitive in the first place. Set a reminder for three to six months before your contract ends, and use that window to properly compare business electricity rates, rather than accepting a rollover. Businesses that let a contract lapse are usually moved onto a deemed or out-of-contract rate, which can sit well above 32p to 40p per kWh, comfortably erasing any saving a smarter schedule might have delivered.
Mistakes to Avoid When Shifting Business Electricity Usage
Moving everything at once. Start with two or three of your biggest, most flexible loads, rather than overhauling the whole operation overnight.
Ignoring the standing charge. A lower unit rate does not always mean a lower bill, so check the full picture rather than just the peak and off-peak numbers.
Forgetting about staff and safety. Never compromise health and safety, food hygiene rules or staff working patterns purely to chase a cheaper rate.
Assuming every supplier prices the same way. Two similarly priced tariffs can have very different peak and off-peak splits, so read the small print or ask a broker to check for you.
Letting the contract roll over. Even the best time-of-use tariff loses its value if you drift onto a deemed rate because nobody diarised the renewal date.
Choosing Business Electricity Suppliers That Reward Off-Peak Use
Not every tariff is built the same way, and not every supplier makes it easy to see whether shifting usage will actually save you anything. When you compare business electricity suppliers, it is worth asking directly whether a tariff has genuine peak and off-peak pricing, what the red, amber and green rates look like in your region, and whether an exit fee applies if your usage pattern changes.
This is exactly the kind of comparison SwitchUrEnergy handles for UK businesses every day. We work with a broad panel of business electricity suppliers, from established names to specialist providers such as Octopus, and put live quotes side by side against your postcode, meter type and usage profile, entirely free of charge. If your business has genuine flexibility in when it uses power, that comparison is usually where the real savings surface.
Frequently Asked Questions
What time is peak and off-peak for UK business electricity?
Peak hours are typically weekdays between 4 pm and 7 pm, when demand on the grid is highest. Off-peak hours generally run overnight, from around midnight to 7 am, plus most of the weekend. Exact times can vary slightly by supplier, region and tariff, so it is worth checking your specific contract.
Do all business electricity tariffs include peak and off-peak pricing?
No. Many standard fixed-rate business tariffs charge a single unit rate all day. You need a time-of-use, multi-rate or half-hourly tariff to actually see different prices for peak and off-peak usage, so this is worth checking specifically when you compare business electricity suppliers.
Does my business need a smart or half-hourly meter to benefit?
In most cases, yes. A standard meter cannot record when electricity was used, only the total, so your supplier has no way to apply different peak and off-peak rates. A smart or half-hourly meter is generally required for any tariff with genuine time-of-use pricing.
Can office-based businesses benefit, or is this only useful for factories?
Offices can benefit too. HVAC, water heating, server backups, EV charging for company cars and even a dishwasher in the staff kitchen can often be timed to avoid the 4 pm to 7 pm window, even if the savings are smaller than on a production line.
Is Octopus Energy the only supplier offering time-of-use business tariffs?
No. Octopus electricity tariffs, including its Agile and Shape Shifters ranges, are a well-known example, but several established UK energy services providers now offer some form of multi-rate or half-hourly pricing for business customers. Comparing several suppliers side by side is the only reliable way to know which structure suits your usage pattern.
How do I find out how much of my usage currently falls in peak hours?
If you have a half-hourly meter, your supplier or a broker can usually break your consumption down by time band. Otherwise, a simple manual audit, noting what runs between 4 pm and 7 pm on a typical day, is a good starting point.
Will switching to a time-of-use tariff always save my business money?
Not necessarily. If your usage is fairly fixed and unavoidably falls in peak hours, such as a busy shop floor at 5 pm, a flat fixed rate may still work out cheaper and more predictable. Time-of-use tariffs suit businesses with genuine flexibility in when they use power.
Final Words
Peak and off-peak pricing will not fix an inefficient business on its own, and it is not a reason to ignore maintenance, insulation or better-specified equipment. But it is one of the few genuine savings available to a business that requires no capital spend at all, just a closer look at the clock. Start with the equipment that has the most flexibility, whether that is a production run, an EV charger, a laundry cycle or a water heater, and build a simple habit of keeping it out of the 4 pm to 7 pm window wherever your operation allows.
The other half of the equation is making sure your tariff actually rewards that effort. If your current contract charges the same rate around the clock, all that scheduling discipline goes to waste. Comparing business electricity suppliers, including time-of-use options from providers like Octopus and other UK energy services, takes a few minutes through SwitchUrEnergy, and it costs nothing to check exactly where your business stands.
Ready to see your numbers? Get a free, no-obligation business electricity quote through SwitchUrEnergy and compare peak and off-peak pricing across trusted UK suppliers in minutes. |