If you want to know how to source corporation tax leads, the first thing worth accepting is that almost nobody searches for a corporation tax accountant the way they search for a plumber. Limited company directors search around the problem. They search for late filing penalties, for what happens when a CT600 is wrong, for whether they can claim a particular cost, or for an accountant in their town who handles companies like theirs.

That changes the sourcing method. Corporation tax work is recurring, annual, and tied to a fixed statutory calendar, which means demand is both predictable in timing and hard to spot in search volume alone. A firm that only watches keyword tools will conclude there is no demand. A firm that combines search data with the public company register will find far more addressable companies than it can service.

This guide sets out the three channels that produce corporation tax enquiries, how to build a targeting list from registry data, how to time outreach against filing deadlines, and where firms lose the leads they have already paid for. We have run this across accounting firms in the UK and US, so the examples are operational rather than theoretical.

There are four distinct pools of limited company work, and each one needs a different approach.

Newly incorporated companies

Companies House publishes new incorporations daily. A company registered this month has its first accounts and first CT600 due roughly 21 months later, and most first-time directors have no adviser at incorporation. This is the highest volume pool and the lowest average fee, because many will stay dormant or fold.

Companies that have filed late before

Filing history is public. A company with a previous late filing has demonstrated that its current arrangement does not work. Late filing penalties for Corporation Tax returns increase for returns with a filing date on or after 1 April 2026, moving from £100 to £200 for a late return, and from £500 to £1,000 where there have been three successive failures. That change gives a concrete reason for a director to reconsider who prepares their return.

Companies switching adviser

Usually triggered by a fee increase, a missed deadline, or growth beyond what the incumbent handles. These are the shortest sales cycles and the highest value, and they arrive mostly through search and reputation rather than outbound.

Companies crossing a complexity line

Group structures, associated companies affecting the small profits rate, R&D claims, or profits moving through the marginal band between the 19% small profits rate and the 25% main rate. These directors know they have outgrown a basic filing service.

Decide which pool you want before you choose a channel. Most firms fail at sourcing because they run one generic campaign at all four.

The public register is the most underused asset in accounting firm marketing. It is free, it is structured, and it tells you things no advertising platform can.

The fields that matter for corporation tax targeting:

• Incorporation date. Sets the first accounting period and therefore the first filing obligation.
• Accounting reference date. Tells you when accounts are due, and by extension the approximate CT600 deadline, since Corporation Tax returns are due twelve months after the end of the accounting period.
• SIC code. Lets you segment by sector, which is how you write outreach that sounds specific rather than generic.
• Filing history. Shows late filings, gaps, and whether accounts arrive early or on the final day.
• Accounts type. Micro-entity, small, or full accounts gives a rough read on turnover band.
• Officer count and appointment dates. A recent director appointment often precedes an adviser review.

Building the list

Filter to your target sector and size, exclude dormant filers if you want fee-paying work, then sort by accounting reference date. You now have a calendar of companies whose filing pressure peaks in a known month. That is your outreach schedule for the next twelve months.

One of our clients, Chris at Thomas Emlyn Ltd, runs an outbound engine built on exactly this data with an AI targeting layer on top. It produces thirty to fifty cold leads a month and five to ten booked meetings. The volume comes from the register. The conversion comes from the targeting being specific enough that the message reads as relevant.

Registry data is personal data where officers are involved, so handle it under UK GDPR with a documented lawful basis and a suppression list. Treat that as a build requirement, not an afterthought.

Search is where the highest intent sits, because the director has already recognised a problem. The volume is lower than firms expect, so structure matters more than scale.

Three keyword layers worth building

Situation keywords. Late CT600 filing, corporation tax penalty appeal, associated companies small profits rate, closing a company with retained profits. Low volume, very high intent, almost no competition from other firms.

Sector plus service keywords. Accountant for construction limited company, accountant for a dental practice, e-commerce accountant. These convert because the director sees their own business described.

Location plus service keywords. Still the largest single pool for most firms, and the reason a Google Business Profile is worth maintaining properly.

What the page has to do

A page that ranks and does not convert is a reporting problem, not a marketing win. Each landing page needs one audience, one problem, one action, and a form that takes under a minute. Prads at Wings Online Filings went from five to seven enquiries a month to fifteen to sixteen, with nine new clients, in the first two and a half months after we rebuilt the SEO architecture and content system around this structure. Niall at OD Accountants saw monthly visitors rise four times over and ten to fifteen enquiries in the first month, because the site was rebuilt around conversion rather than adding more articles.

Paid search sits alongside this for the terms you cannot rank for quickly. Treat it as a way to buy data on which messages convert, then feed the winners back into your organic pages.

Corporation tax has a fixed rhythm, and that rhythm is your campaign calendar. Accounts are due nine months after the accounting reference date for a private company, the Corporation Tax payment falls nine months and one day after the end of the accounting period, and the CT600 is due twelve months after period end.

That gives you predictable windows where a director is most receptive.

The four windows

1. Two to three months before the accounts deadline. The director knows the date is coming and has not started. Highest receptivity to a switch conversation.
2. Immediately after a penalty. Filing history shows you who has been penalised. With penalties for returns filed late rising for filing dates from 1 April 2026, the cost of a poor arrangement is more visible than it used to be.
3. Six to eight weeks after incorporation. The first-time director has opened a bank account and started trading, and is now realising what filing involves.
4. January and April. Personal tax season and the start of the new tax year both push directors into reviewing their whole arrangement, including the company.

Map your registry list against these windows and you have a twelve-month outbound schedule where every contact has a reason to exist. Compare that with the alternative most firms run, which is a burst of activity when the pipeline looks thin. Timing does more for response rate than copy does.

Ask on AccountingWEB about lead sellers and the responses are consistently negative. Directory marketplaces get described as a disaster, referral panels as a waste of money, and the recommended alternative is usually networking or LinkedIn. That feedback is worth taking seriously, but the diagnosis is often wrong.

The problem with most bought leads is structural, not moral:

• The lead is sold multiple times. You are one of four or five firms calling the same person within an hour, so the conversation becomes a price comparison.
• No qualification layer. A limited company with a £900 turnover and a sole trader curious about incorporating arrive in the same inbox as a group with three trading subsidiaries.
• You do not own the asset. Stop paying and the flow stops instantly. A ranked page and a registry-based outbound list keep working.
• Attribution is measured at the wrong point. Firms track cost per lead. The only number that matters is cost per client won, set against the lifetime value of a recurring compliance client.

If you do test a paid source, run it as a controlled experiment. Fixed budget, fixed period, one tracked phone line or form, and a decision rule set in advance. Score every lead on arrival and record why the ones you lost were lost. Directories like Clutch will show you reviews and typical project costs for providers, which helps with shortlisting, though no directory can tell you whether a channel suits your firm's fee level and capacity.

Sourcing more corporation tax leads makes your admin problem worse unless the handling system exists first. This is where most growth attempts stall in firms with 2 to 20 staff, because the partners who close work are also the people preparing returns in the same week.

The four components

Qualification at the point of enquiry. The form should ask enough to grade the lead: company or sole trader, turnover band, accounting reference date, current adviser, reason for enquiring. One of our clients, Annabel, has enquiries screened automatically so her calendar only carries higher value opportunities.

Speed of first response. Response time beats sales skill for a first enquiry. An automated acknowledgement with a booking link, sent within a minute, holds attention while the enquiry is still fresh.

Structured follow-up. A director comparing three firms decides over about two weeks. A sequence of four to six touches across email and SMS, each with a specific reason to make contact, is what closes the gap between quoted and signed.

Onboarding that runs itself. Engagement letter, anti-money laundering checks, authorisation, records request, and software setup should be a workflow, not a checklist someone remembers. Without it, the tenth new client costs you more than the first nine combined.

Build these four before you increase volume. Otherwise you are paying to generate enquiries that quietly expire in an inbox.

A sequence that works for a firm of 2 to 20 staff, starting with the cheapest steps. Each stage should be functioning before you start the next.

Five recurring patterns from working with accounting firms on corporation tax lead generation.