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Time of Use Tariffs for Business Explained

Time-of-use (ToU) business electricity products price kWh differently across the day. In the UK they sit at the intersection of half-hourly settlement data, supplier hedging, and—often—pass-through distribution charges that already vary by time band. A ToU quote is not “greener” or “fairer” by default; it simply transfers risk and reward to how well you can shape demand. This guide explains what to verify in the schedule, how ToU interacts with DUoS, and when a fixed single-rate remains the rational choice.

Next step: If you use under about 50,000 kWh a year, you can get a quote in under 90 seconds online — fast, no obligation. Larger supply, half-hourly metering, or prefer chat? Use the contact page.

Retail ToU versus network time bands

Your supplier invoice is a stack of commodity, policy, and sometimes network elements. On flexible or pass-through products, distribution use-of-system (DUoS) may be listed explicitly and can reference red/amber/green style periods that do not line up word-for-word with the supplier’s marketing labels. That mismatch is a common source of surprise when a site adopts EV charging or shifts production but sees network pounds move differently from energy p/kWh.

Ofgem’s oversight of suppliers focuses on licence compliance, including accurate billing and, for microbusinesses, clearer renewal communications. It does not pick your tariff geometry. Finance therefore needs a scenario model: take 12 months of half-hourly kWh, map them to each price band in the draft contract, then repeat under a stress case (e.g. 15% more peak kWh). Our night rate electricity for business guide explains why register-level thinking still matters when “off-peak” language appears.

Procurement questions that separate serious ToU from branding

Ask for the principal terms document, not a slide. Confirm how each half-hour is classified when clocks change, how holidays are treated, and whether any band is indexed to a published series. If the product is partially fixed and partially passthrough, obtain the reconciliation method so you are not arguing averages six months later.

Climate Change Levy still applies to qualifying electricity consumption at the relevant rate unless a statutory relief applies to your organisation; ToU does not change levy mechanics. VAT treatment follows HMRC rules for your activities. When comparing to a fixed single-rate offer, use the workflow in how to compare business energy quotes so standing charges and passthrough lines stay visible.

Operational playbooks that actually move kWh

Winning ToU sites combine building management defaults with accountable operators. Examples include staged HVAC start-ups, thermal storage for hot water, batching compressors into shoulder periods, and fleet charging rules capped by time. Each control should log exceptions; otherwise peak drift erodes the business case within one hot week or a busy retail month.

Smaller businesses without half-hourly settlement can still see time-differentiated offers, but the value proposition is weaker if reads are infrequent and estimates dominate. In those cases weigh simplicity and dispute risk against theoretical p/kWh savings.

When to keep a simple fixed rate

Fixed single-rate contracts remain appropriate when demand is inflexible, staffing cannot honour schedules, or treasury wants predictable accruals. They also suit organisations that lack data literacy to police bands monthly. There is no regulatory preference—only fit to load shape and governance.

ToU implementation checklist

UK market context: what Ofgem does and does not decide

Ofgem’s role is to protect consumers through supplier licensing, enforce standards on billing accuracy, and—where applicable—ensure microbusinesses receive clearer information at renewal. It does not set your optimum tariff geometry. That remains a commercial decision between you, your supplier, and any broker, provided contract terms are transparent. When markets are volatile, some suppliers withdraw simple ToU products or tighten credit; keep a fallback fixed quote on file before you commit operations to a load-shifting playbook.

Industry settlement under the Balancing and Settlement Code means half-hourly data eventually drives what many invoices reconcile to, even if operational teams only see monthly totals. Engage your data collector or portal vendor early if you plan major equipment moves: stale loss factors or CT ratios distort band allocation and undermine the very savings ToU was meant to unlock. Document any disputes with timestamped HH extracts so escalations to the supplier or, for eligible complaints, the Energy Ombudsman rest on facts rather than estimates.

Microbusinesses should still file renewal paperwork methodically: a ToU matrix that looked brilliant in a spreadsheet can auto-roll to a poor default if nobody responds in the statutory window. Pair procurement with a simple calendar note fourteen days before each supplier “action required” email so operations and finance both see it.

Related guides

See half-hourly vs non-half-hourly meters, maximum demand charges explained, and the energy hub.