An expression of interest (EOI) email is often your first formal contact with a buyer. In UK procurement, it might be a response to early market engagement, a Prior Information Notice (PIN), soft market testing, or a supplier invitation before the full tender lands. It doesn’t need to be long — but it does need to be clear, relevant and credible.

Think of it as a short supplier expression of interest. You’re saying:

1. We’re interested in this opportunity.
2. We’re a credible fit to deliver it.
3. Here’s why you should include us in the next stage.

Some buyers use EOIs to shortlist suppliers for tender lists. Others use them to understand market capability before shaping the specification. Either way, your job is to show that you’re worth their attention. EOIs are common across all industries but are particularly prevalent in IT, Construction & Infrastructure contracts and healthcare.

What to include

A good EOI email for a UK public sector opportunity usually covers:

1. A direct statement of interest

Reference the opportunity clearly. Include any tender ID, project name, or portal reference.

Example:

“Thank you for publishing the early market engagement for [Project/Service]. We’d like to express our interest in participating in the forthcoming procurement.”

2. A one-paragraph summary of who you are

Keep it punchy: what you do, where you operate, and who you serve. If you’re an SME, say so — many authorities actively want SME participation.

3. Your relevance to the requirement

This is the most important part. Show alignment to the buyer’s goals. Use two or three bullet points connecting your services and outcomes to their need.

Example bullets:

• Experience delivering [service] for UK public sector / regulated clients
• Capacity to mobilise across [region] within [timescale]
• Proven outcomes in [cost saving / compliance / service improvement]

4. Evidence in miniature

Mention one or two credible examples: a project like theirs, a framework you’re on, or a measurable outcome. Don’t attach a 20-page brochure unless asked.

5. Your contact details and next steps

Make it easy to follow up. Offer a short call or capability discussion.

What not to do

• Don’t paste a generic sales email. Buyers spot this instantly.
• Don’t oversell or exaggerate. Procurement teams value accuracy and risk awareness.
• Don’t go long. An EOI email is not a tender response. Aim for 150–300 words unless the buyer asks for more.
• Don’t ignore instructions. If they ask for a capability statement, provide it. If they ask for specific headings, follow them.

A simple EOI email structure/template

Subject: Expression of Interest – [Opportunity Name / Reference]

Hello [Name/Team],

Thank you for the opportunity to engage with the upcoming procurement for [Opportunity]. We would like to formally express our interest in participating.

[Company] is a UK-based [SME / supplier] specialising in [core service]. We support [types of clients] across [regions], with particular strength in [relevant area].

We believe we are well aligned to this requirement because:

• [Relevant capability #1 tied to need]
• [Relevant capability #2 tied to need]
• [Relevant capability #3 tied to need]

By way of evidence, we have recently delivered [brief example] achieving [result/outcome]. We are also currently accredited/on framework [if applicable].

We’d welcome the chance to discuss our capability further or respond to any market-testing questions. Please contact me on [phone/email].

How a bid writer can help with EOIs

EOIs are short, but they set the tone. A well-written EOI can get you invited to tender, while a weak one leaves you off the list.

Our Bid Writer Consultancy supports SMEs with EOIs, capability statements and early engagements. We use AI to speed up drafting but rely on professional bid specialists to keep content tailored, compliant and realistic. That means you respond quickly without sacrificing quality.

Need an EOI drafted fast? We can turn around EOIs and tender documents within 72 hours for a flat fee of *£1500 + VAT, giving you a confident entry into the procurement process.

*Our flat fee covers up to 8,000 words. We’ll confirm the cost before work begins if we think the submission will be longer than this.