How The IPO Process Works In The UK

Thinking about taking your company public? An initial public offering (IPO) can be a powerful way to raise capital, build credibility and create liquidity for early investors. But the UK IPO process is complex, highly regulated and time‑consuming - it pays to understand the roadmap before you dive in.

In this guide, we’ll walk you through how the IPO process works in the UK, common pitfalls for small and scaling businesses, and the key legal steps to get right from day one so you’re IPO‑ready when the time is right.

Is An IPO The Right Move For Your Business?

Before you start planning an IPO, make sure it truly fits your strategy and stage. Going public isn’t just a fundraise - it fundamentally changes your obligations as a company and as directors. You’ll be subject to ongoing disclosure rules, market scrutiny and corporate governance requirements that are far more demanding than private company life.

Consider the following:

• Capital needs and use of proceeds - do you have a clear growth plan that justifies the funds you’ll raise?
• Track record - most markets expect at least a three‑year financial track record with audited accounts.
• Scale and systems - are your finance, legal and compliance functions robust enough for public company life?
• Shareholder dynamics - are founders and early investors aligned on dilution, lock‑ups and timing?
• Costs and timeline - underwriting fees, legal and accounting costs and internal time will be significant.

It’s also worth weighing private alternatives - for example, a private placement, venture round or using an Advanced Subscription Agreement to bridge to a larger raise - especially if you need capital quickly and want to avoid public company obligations for now.

Which UK Market? Main Market vs AIM

In the UK, most companies list on either the London Stock Exchange Main Market or AIM (the Alternative Investment Market). Each has different eligibility, disclosure and governance requirements.

Main Market (Premium or Standard Listing)

The Main Market is generally for larger, more established companies. A Premium listing brings the most stringent requirements, including compliance with the UK Corporate Governance Code, pre‑emption rights and related party rules. A Standard listing is typically less prescriptive but still demanding. You’ll work with an FCA‑approved sponsor and comply with the FCA’s Listing Rules, Prospectus Regulation Rules and Disclosure Guidance and Transparency Rules.

AIM

AIM is designed for growth companies seeking more flexibility. You’ll be advised by a Nominated Adviser (Nomad) who assesses your suitability for admission and guides you through the rules. AIM has different reporting expectations and ongoing obligations compared to the Main Market, which can suit earlier‑stage businesses - but standards are still rigorous.

Whichever route you choose, expect a deep dive into your finances, governance and risk management. It’s wise to start aligning your internal processes well in advance.

The UK IPO Process Step By Step

Every listing is unique, but most IPOs follow a broadly similar journey. Here’s how it typically unfolds.

1) Early Readiness And Governance Upgrades

Start with a high‑level readiness assessment. Advisors will review your corporate structure, financial reporting, tax, governance and legal documentation. Many companies adopt new articles and strengthen board procedures to meet market standards. This is also the stage to tidy up your cap table, confirm option grants and align founder and investor rights.

You’ll normally need shareholder approvals for pre‑IPO actions (for example, new share authorities, pre‑emption disapplication or adopting new articles). Plan ahead for the right approvals using clear Board Resolutions and, where required, Special Resolutions. New listing‑ready articles often replace legacy provisions that don’t work well in a public company setting.

2) Appoint Your IPO Team

You’ll assemble a team including a sponsor (Main Market) or Nomad (AIM), legal counsel, reporting accountants, tax advisors, PR/IR consultants and a registrar. Your internal team should include a project lead, CFO or finance lead, and company secretarial support to manage documentation and timelines.

3) Due Diligence

Expect intensive financial, legal and commercial due diligence. Legal diligence will cover corporate history, share issuances, material contracts, IP ownership, employment, litigation and regulatory compliance. Accurate records matter - for instance, maintaining your statutory registers and issuing share certificates and member registers correctly helps avoid last‑minute delays.

4) Prospectus Or Admission Document

You’ll prepare a prospectus (Main Market) or an AIM admission document. This is the core investor document describing your business, financials, risks and the terms of the offer. The drafting is supported by formal verification to ensure statements can be substantiated. The FCA will review a Main Market prospectus, while AIM admission documents are reviewed by your Nomad.

5) Corporate Actions And Reorganisations

Many companies implement pre‑IPO steps such as group simplification, converting preference shares, capital re‑denomination, or employee option plan changes. Where you issue new shares, consider how you’ll account for proceeds and any share premium created. If any existing shareholders are selling, a well‑drafted Share Sale Agreement will set out terms, warranties and transfer mechanics, and you’ll need to factor in any stamp duty on shares for off‑market transfers.

6) Marketing, Pricing And Allocation

Once regulatory approvals are in sight, your banks will run investor education and bookbuilding. The board will approve pricing and allocation, often under tight timelines. You’ll also finalise any underwriting or placing agreements and announce the offer details.

7) Admission And Beyond

On admission, your shares begin trading and the company transitions into life as a listed business. From that day forward, you must comply with ongoing obligations - including timely disclosure of inside information, publishing financial reports, managing insider lists and dealing code compliance, and keeping the market informed about significant developments.

Key Legal Foundations To Get IPO‑Ready

Even if an IPO is 12–24 months away, laying your legal foundations now will save you stress (and cost) later. Here are the areas most listings teams focus on early.

Shareholder Alignment And Pre‑IPO Clean‑Up

Clarity among shareholders is essential. Any historic side‑letters, bespoke rights or investor protections should be identified and, where appropriate, consolidated into a clean, listing‑ready capital structure. For private companies, having a robust Shareholders Agreement during the scale‑up phase helps avoid disputes and sets expectations around exits, drag‑along, tag‑along and information rights.

Articles And Authorities

Most companies adopt fresh, listing‑ready constitutional documents before admission. If your current articles are outdated or inconsistent, consider replacing them using a set of Articles of Association tailored for your future obligations. You’ll also prepare shareholder authorities to allot shares and disapply pre‑emption rights under the Companies Act 2006 - typically via ordinary and special resolutions.

Employee Incentives

Public‑company‑grade incentives help attract and retain talent, and investors will look closely at your schemes. If you’re still private, tax‑efficient EMI Options can be a strong tool, with a view to migrating to listed‑company LTIP arrangements later. Ensure grants, vesting and leaver provisions are documented properly, and that your share plan aligns with lock‑ups and any pre‑IPO reorganisations.

Material Contracts And IP Ownership

Your material contracts (customers, suppliers, licensors, finance) should be assignable or already in the listed entity. Confirm you own or have valid licences to your core IP, and that contractor agreements include proper IP assignment provisions. Any change‑of‑control clauses or termination rights triggered by listing should be identified early so you can plan workarounds.

Financial Reporting And Controls

Upgrade your financial reporting to meet market expectations. This usually involves audited accounts for the required track record period, robust IFRS compliance, forecasting and a documented system of internal controls. Board committees (audit, remuneration, nominations) and clear terms of reference are typically established, and director independence is considered carefully.

Regulatory And Ongoing Compliance After Listing

Once listed, compliance moves from a project to business‑as‑usual. The legal framework includes the FCA’s Listing Rules, Prospectus Regulation Rules (for future offerings), Disclosure Guidance and Transparency Rules, and the UK version of the Market Abuse Regulation (MAR). On AIM, the AIM Rules for Companies and MAR apply, with oversight by your Nomad.

Disclosure And Inside Information

You must disclose inside information to the market as soon as possible unless a limited exemption applies. That means strengthening internal processes for identifying and escalating price‑sensitive information, maintaining insider lists and setting up a dealing code for directors and senior managers (PDMRs).

Financial Reporting

Prepare for half‑yearly and annual reporting, audited accounts and timely publication deadlines. Many companies enhance their finance team and implement an annual reporting calendar to stay ahead of requirements.

Shareholder Meetings And Approvals

Annual general meetings, periodic authorities to allot shares, buybacks and significant transactions will all require careful planning and, in some cases, shareholder approval. Make sure your secretariat and legal teams are comfortable preparing notices, coordinating polls and recording decisions with the right mix of board resolutions and shareholder approvals.

Common Pitfalls Small Businesses Can Avoid

IPO projects often slow down because of issues that could have been fixed months earlier. Here are the recurring ones we see - and how to stay clear of them.

• Untidy cap tables - missing or inconsistent share issuances, option records or transfers. Keep your registers current and issue documents promptly, including share certificates.
• Legacy shareholder rights - complex or conflicting investor protections can spook new investors. Use pre‑IPO reorganisations and refreshed articles to streamline your rights stack.
• Contract gaps - missing assignments, weak IP clauses or change‑of‑control triggers. Triage key contracts early and agree amendments with counterparties in good time.
• Late approvals - waiting to the last minute to pass share authorities or adopt new articles. Schedule your special resolutions early and build AGM/EGM lead times into your plan.
• Misaligned incentives - option terms or leaver provisions that clash with underwriting lock‑ups or market expectations. Review your schemes and consider adjustments alongside the IPO timetable.
• Confusion over proceeds - unclear accounting for new money vs. vendor sell‑downs. Ensure the offer structure, new share authorities and any Share Subscription Agreement terms line up.

Alternatives To An IPO (For Now)

It’s absolutely fine to decide that listing isn’t quite right - or not right yet. There are credible alternatives to finance growth while you strengthen your track record and systems.

• Private placements or growth equity led by institutional investors.
• Convertible instruments (e.g., ASAs, SAFEs or notes) - a subscription in advance can provide runway while deferring valuation to a later round.
• Strategic partnerships or minority sell‑downs via a negotiated share sale to an industry investor.
• Employee ownership to support retention and growth through EMI options in the scale‑up phase.

If you take one of these routes, keep your “IPO file” in good order - governance upgrades, tightened contracts and proper shareholder authorities are just as valuable for private rounds as they are for public ones.

Key Takeaways

• Check whether listing is the right fit for your stage and strategy - AIM and the Main Market have different requirements, timelines and costs.
• Start early on governance: refresh your articles, line up the right board resolutions and prepare shareholder approvals using the correct mix of ordinary and special resolutions.
• Get your cap table, share registers and incentive schemes in perfect order - messy records create delays and can threaten investor confidence.
• Expect intensive diligence, prospectus drafting and verification - build strong internal controls and board committees early so you’re ready for public company obligations.
• Plan the offer mechanics carefully: authority to allot, pre‑emption disapplication, how proceeds are accounted for (including any share premium) and whether any vendor selling triggers stamp duty.
• Consider alternatives if timing isn’t right - private rounds, a simple ASA or employee options can help you grow while you get IPO‑ready.

If you’d like tailored advice on preparing your company for the IPO process - from shareholder approvals to updated articles and offer documentation - you can reach us at 08081347754 or team@sprintlaw.co.uk for a free, no‑obligations chat.