Around 1,700 customers affected by possible breaches of contract reveals Consumer and Markets Authority’s new Heating Oil Market Study

The Competition and Markets Authority (CMA) recently concluded its study into the UK heating oil market – and its findings carry important lessons for consumers and businesses alike.

Background

Roughly 1.5 million households in the UK rely on heating oil, with particularly high concentrations in Wales, Herefordshire, the Cotswolds, Cambridgeshire and Norfolk. For many of these households, which are often in rural areas beyond the reach of the mains gas network, heating oil is not a lifestyle choice but a necessity. Unlike mains gas and electricity, heating oil is typically bought in large volumes, meaning households can face bills of around £500 or more at a time. Prices can fluctuate significantly, and consumers frequently have limited options when it comes to choosing a supplier.
The CMA launched its market study after conflict in the Middle East caused significant disruption to the sector. At their peak, average retail price rose by 92% – from around 64p per litre in February 2026 to 123p per litre in April 2026. In practical terms, this meant that consumers may have paid around £200 more for a typical 500-litre order.

Findings

The CMA concluded that the market is “generally competitive” and that “suppliers have not profited materially from the crisis”. However, it found that heating oil customers are not as well protected as those connected to the gas and electricity networks. These gaps included: (i) the absence of consistent standards of support for vulnerable customers; and (ii) no access to alternative dispute resolution where a customer cannot resolve their issue with a supplier. These gaps become especially problematic during periods of volatility, when households may face substantially higher prices, uncertainty over deliveries, and fewer options for urgent supply.

The CMA also found that around 1,700 customers were affected by possible breaches of contract when suppliers cancelled their orders as the crisis unfolded. Whilst those customers received refunds on their original orders, many had to re-order at significantly higher prices or go without fuel.

The CMA’s Next Steps and Recommendations

Following CMA engagement, a number of suppliers have agreed to compensate affected consumers. However, not all have done so, and the CMA is preparing to take enforcement action against firms that have failed to compensate customers voluntarily.

The CMA has also recommended that the UK and devolved governments introduce a new, proportionate regulatory regime for heating oil suppliers. This should require suppliers to register and meet minimum standards – covering how prices are quoted, how cancellations are managed, and giving households access to independent dispute resolution. The CMA also recommends a register for vulnerable households, clearer signposting of payment plans and minimum purchase volumes, and a review of rules around minimum order volumes to allow people to buy smaller amounts.
Below, we explore the heating oil study as a practical example to explain what the CMA does, how its work affects you, and what businesses should do if they find themselves under the CMA’s spotlight.

Consumers: What does the CMA do for you?

Q: What is the CMA, and why should I care about it?
A: The CMA is the UK’s principal competition and consumer protection authority. Its role is to ensure that markets work well for consumers – that prices are fair, businesses compete honestly, and consumers are not misled or treated unfairly.

Q: Does the CMA deal with markets more broadly?
A: Unlike sector-specific regulators (such as Ofgem for energy), the CMA’s remit spans the whole economy – which is why it was able to address the heating oil market, a market that historically had little regulatory oversight. Any market where consumers may be at risk of unfair treatment can attract the CMA’s attention.

Q: Why does it matter that heating oil is unregulated?
A: Customers connected to gas and electricity networks benefit from protections overseen by Ofgem – including standards of support for vulnerable consumers and a requirement for energy suppliers to be members of an independent ombudsman scheme. As the study shows, gaps such as these leave consumers particularly exposed during periods of price volatility or supply disruption, with fewer options for redress when things go wrong.

Q: What can I do if I think I have been treated unfairly by a supplier?
A: The right course of action depends on the nature of the complaint. For straightforward issues, such as a billing error or missed delivery – raising a complaint directly with the supplier is a sensible first step. If the supplier does not resolve the matter, you can escalate the complaint via the appropriate channel, for example through Trading Standards or directly to the CMA.

However, where an issue is more complex – for example a possible breach of contract, misleading pricing, or a pattern of unfair treatment – we would recommend seeking legal advice early. This is particularly important in unregulated markets like heating oil, where consumers do not yet have access to an independent ombudsman or alternative dispute resolution (ADR) scheme.

For Businesses: The CMA is Investigating Your Sector – What Now?

Q: How might a CMA investigation affect my business?
A: A CMA market study can lead to recommendations for new regulation across an entire sector – as the heating oil study has done. If the CMA identifies concerns about a specific business’s or markets’ conduct, it may open a formal investigation, seek binding undertakings (commitments to change practices or compensate consumers), or pursue enforcement action. For competition law breaches, fines of up to 10% of worldwide annual turnover are also possible. Even where no formal finding is made, the reputational impact of being publicly named in a CMA investigation can be significant.

Q: What should I do if the CMA contacts my business?
A: There are several immediate steps you should take:

1. Do not ignore it. CMA correspondence should be treated with urgency. The CMA has statutory powers to compel businesses to provide information and documents, and failure to comply can result in penalties.
2. Seek specialist legal advice early. The way you respond in the early stages can significantly affect the outcome.
3. Preserve all relevant documents. Once you are aware of an investigation, you are under an obligation not to destroy potentially relevant materials.
4. Understand your rights. Businesses have procedural rights during CMA investigations, including the right to make representations. Legal advisers experienced in CMA matters can help you exercise those rights effectively.
5. Engage constructively. As the heating oil study illustrates, the CMA will typically seek voluntary compliance before escalating to enforcement. Businesses that engage early and in good faith are generally better placed to influence the outcome.

Q: Could this happen to my sector?
A: Yes. The CMA’s remit covers all sectors of the economy and it can launch a market study on its own initiative, in response to complaints, or following a referral. Industries that are currently lightly regulated, involve essential goods or services, or are exposed to supply chain volatility may be particularly susceptible. The heating oil study is a clear reminder that no sector is immune from scrutiny.

Key Takeaways

Key takeaways for consumers:

• The CMA exists to protect you and has to power to investigate entire markets, take against businesses that treat customers unfairly, and push for stronger protections where gaps exist.
• Not all markets are equally well regulated and if you rely on goods or services that sit outside a formal regulatory framework: you may have fewer options for redress when things go wrong.
• If you believe you have been treated unfairly, depending on the nature of the issue, there may be routes available to you – from escalating a complaint through Trading Standards to seeking legal advice on a potential claim.

Key takeaways for businesses:

• The CMA’s remit covers all sectors of the economy. If your industry is lightly regulated, involves essential goods or services, or is exposed to supply chain volatility, you may be particularly susceptible to scrutiny.
• A CMA investigation can result in binding undertakings, enforcement action, significant fines, and reputational damage – even before a formal finding is made. Early and constructive engagement is in your interests.
• If the CMA contacts your business, act promptly: seek specialist legal advice, preserve relevant documents, understand your procedural rights, and cooperate in good faith.