MCP for UK Businesses: HMRC Tax, Companies House & Land Registry Use Cases (2026 Guide)

Most MCP guides focus on American tools and workflows. If you’re running a business in the UK, there’s a specific set of use cases that are immediately practical — and more accessible than they look.

This guide covers the UK-specific MCP integrations I’ve tested extensively: Companies House due diligence, HMRC tax calculations, Land Registry property research, and GOV.UK guidance parsing.

Companies House: Due Diligence in Under Five Minutes

Companies House maintains one of the most comprehensive public business registries in the world, and it has an open, free API. I spent an afternoon setting up an MCP connection to it, and the result changed how I do supplier research entirely.

With this connection, I can ask Claude to pull a company’s registration details, check their confirmation statement filing history, see who the current directors are, look up any county court judgements on record, and summarise the overall picture — all in a single prompt. What I used to spend forty minutes on now takes four.

The practical prompt I use most often:

“Using the Companies House connection, look up [Company Name], list the current directors and their other active directorships, flag any overdue filings, and give me a one-paragraph risk summary.”

For anyone doing supplier vetting, client due diligence, partnership research, or simply checking whether a new contact’s company is legitimate before you engage, this is worth the setup time ten times over. The Companies House MCP server is available through standard open API documentation, and in my testing it’s one of the more reliable connections I’ve used — the API itself is well-maintained and rarely goes down.

💡 Insider Tip: Combine Companies House with a web search MCP server for maximum due diligence power. Claude will cross-reference the official filing data with recent news, press mentions, and LinkedIn profiles automatically if you ask it to. I’ve caught things this way that a manual search would have missed.

HMRC UK: Making Tax Digital and Smarter

Tax is the area where I’ve heard the most scepticism about AI from UK business owners — understandably, given the stakes. But in my experience, the use case here isn’t “let Claude do your taxes.” It’s “let Claude make sense of HMRC’s guidance and calculate estimates so you don’t have to decode it yourself.”

What’s Actually Available

HMRC’s Making Tax Digital initiative has moved more and more of the UK tax system online, creating structured data that Claude can work with productively through MCP connections. The practical capabilities break down into several categories:

1. Tax Calculations and Estimators

HMRC provides official calculators covering Income Tax, National Insurance, VAT, PAYE, Corporation Tax, Capital Gains Tax, Inheritance Tax, Stamp Duty Land Tax, and IR35 status checks. With an MCP connection to these resources, Claude can query current tax rates, thresholds, and allowances directly rather than you navigating between GOV.UK pages and your spreadsheet.

Practical use: Instead of manually checking whether your projected turnover triggers VAT registration or calculating your estimated tax bill for the year, you can ask:

“Based on these figures, what would my estimated Income Tax and National Insurance be for this tax year under the current HMRC thresholds?”

“I’m self-employed with these expenses — what’s my taxable profit and what payment on account should I expect in January?”

“Check the current VAT threshold and tell me whether this projected turnover would trigger a registration requirement.”

I tested this with my own figures for one quarter and compared the output against my accountant’s calculation. They matched.

2. Making Tax Digital (MTD) API Integration

For businesses already enrolled in Making Tax Digital, MCP servers can connect to HMRC’s official APIs to:

• Trigger and retrieve Self Assessment tax calculations
• Check MTD subscription status for specific tax years
• Query employment and benefits data reported by employers
• Submit and retrieve quarterly business updates (for MTD-enrolled businesses)
• Check VAT submission status and registration details

Practical use: For accountants and bookkeepers managing multiple clients, this transforms workflows:

“Which of my retail clients have overdue VAT returns this quarter?”

“Using the Making Tax Digital connection, retrieve the current tax calculation for [client name] for 2025/26 and show me their Income Tax and NIC breakdown.”

3. IR35 and Employment Status

HMRC’s Check Employment Status for Tax (CEST) tool guidance can be queried through MCP to help contractors think through their IR35 position. This isn’t legal advice, but it’s a structured thinking tool that knows the current rules and can walk through the standard status indicators.

Practical use: Before engaging a tax adviser:

“Walk me through the IR35 status indicators for this contract arrangement: [describe working pattern, control, substitution rights]. What does HMRC’s guidance suggest about each factor?”

4. National Insurance Contributions

Director’s NI calculations, employee NI thresholds, and self-employed Class 2/Class 4 contributions can be calculated against current HMRC rates.

Practical use:

“I’m a company director taking £[X] salary and £[Y] dividends. What’s the most tax-efficient split for 2025/26 given current NI thresholds?”

The Critical Distinction

This is NOT tax preparation software. HMRC MCP connections don’t file your returns, submit VAT, or handle official communications with HMRC. They don’t replace a qualified accountant for anything consequential.

What they DO is:

• Help you understand your numbers before the accountant conversation
• Check current rates and thresholds instantly
• Run “what if” scenarios for tax planning
• Parse HMRC guidance for your specific circumstances
• Estimate liabilities for budgeting purposes

Always verify with a professional before acting on tax calculations. But as a way to prepare, plan, and understand the rules, it’s genuinely useful.

How I Actually Use This

The prompt patterns that work best:

For threshold checks: “What’s the current VAT registration threshold for 2025/26? My projected annual turnover is £[X] — do I need to register?”

For tax planning: “Compare three scenarios: (A) salary £12,570 + dividends £40,000, (B) salary £25,000 + dividends £27,570, (C) salary £50,000 + dividends £2,570. Which minimizes total tax and NI for a one-person limited company director?”

For IR35 due diligence: “Review this contract against HMRC’s IR35 indicators: [paste key terms]. What are the red flags and what strengthens an outside-IR35 position?”

For compliance checks: “I’m self-employed with trading income £[X] and allowable expenses £[Y]. What’s my taxable profit, and what Class 2 and Class 4 NIC would I owe?”

What This Changed

Before having HMRC data accessible through MCP, answering “should I register for VAT next month?” meant:

1. Finding the current threshold on GOV.UK (hoping I was reading the right tax year)
2. Manually totaling my rolling 12-month turnover
3. Checking exemptions and special schemes
4. Still not being certain whether projected growth would tip me over

Now it’s one question, answered in seconds, with current thresholds automatically applied.

The same pattern holds for dividend vs. salary optimization, payment on account calculations, and IR35 risk assessment. These aren’t trivial calculations — getting them wrong costs real money. Having instant access to current HMRC rules and calculators means you enter professional advice conversations already understanding your position.

Security and Compliance Note

HMRC MCP servers that access the official Making Tax Digital APIs require OAuth authentication and must be authorized through your Government Gateway account. This means:

• You control exactly which data the connection can access
• Read-only connections cannot submit returns or change your records
• Authentication tokens expire and must be renewed

Always review permissions carefully before connecting. If you’re using MCP for planning and estimation (checking thresholds, running calculations), you don’t need write access to your HMRC account — read-only or reference-data-only connections are safer.

Land Registry and Property Research

Land Registry and Property Research

For anyone involved in property — whether you’re a landlord, a conveyancer’s client, a small developer, or simply a curious buyer — HM Land Registry’s datasets are publicly available and accessible via MCP. What I initially connected as a simple price-paid experiment has turned into something far more comprehensive.

What’s Actually Available

The HM Land Registry MCP server gives access to six major bulk datasets covering England and Wales:

1. UK Companies That Own Property (CCOD)
Every freehold and leasehold title where the registered owner is a UK company, corporate body, or LLP. This excludes private individuals and charities, which means you’re looking at corporate property portfolios only.

Practical use: If you’re vetting a supplier or potential business partner, you can now see exactly what property they own, where it’s located, and whether it’s freehold or leasehold. I used this when researching a logistics company before signing a contract — their registered property holdings told me more about their operational scale than their website did.

2. Overseas Companies That Own Property (OCOD)
Same structure as CCOD, but for foreign-incorporated companies. Includes the country of incorporation for each proprietor.

Practical use: Foreign investment tracking, transparency checks, and identifying offshore ownership structures. If you’re a journalist, compliance officer, or simply researching who actually owns a development in your area, this dataset answers questions that used to require paid services.

3. Registered Leases
Details from every lease exceeding 7 years that’s been registered, including term length, date of lease, premium paid, and alienation clauses.

Practical use: Lease expiry analysis for portfolio management, ground rent exposure research, or identifying short-lease properties before purchase. For anyone buying leasehold, this is critical due diligence that’s now automated.

4. Restrictive Covenants (RES_COV)
All registered land and property with restrictive covenant entries on the title.

Practical use: Before submitting a planning application or purchasing land for development, you can check whether restrictive covenants will block your intended use. This used to require manual title checks through a solicitor — now you can screen properties at scale before engaging professionals.

5. National Polygon Service (NPS)
Geospatial boundaries of registered land titles in shapefile format. Requires GIS software like QGIS to process, but if you’re doing spatial analysis, it’s invaluable.

Practical use: Mapping exact title boundaries, overlay with flood risk or planning data, land assembly feasibility studies. For developers and planners, this is the difference between guessing and knowing.

How I Actually Use This

The prompt structure I’ve found most useful is:

“Using the Land Registry MCP connection, pull the CCOD dataset for companies registered in [postcode area]. Show me all corporate-owned properties, their tenure type, and any patterns in ownership concentration.”

For due diligence on a specific company:

“Look up [Company Name] in the CCOD dataset. List all properties they own, whether freehold or leasehold, and their registered addresses. Cross-reference with their Companies House filing address.”

For lease research before a purchase:

“Check the Registered Leases dataset for [address or title number]. What’s the remaining term, was there a premium paid, and are there alienation restrictions?”

The Practical Advantage

What makes this genuinely useful is that it’s no longer theoretical. Walking into a property negotiation knowing:

• The exact recent sold prices of comparable properties on the same street (price-paid data)
• Whether similar properties have restrictive covenants that might affect value
• The lease terms and expiry dates for comparable leaseholds in the area
• Who else owns property nearby and whether there’s corporate concentration

…gives you a meaningful information advantage that used to require a solicitor, a surveyor, and several days of manual research.

Technical Note

These are bulk datasets — some files are several GB when uncompressed. The MCP server provides metadata and secure download links, not inline queries of individual records. For one-off property lookups by postcode, you’d use the separate Price Paid or Linked Data tools. But for portfolio analysis, area research, or pattern detection across multiple properties, the bulk datasets are what you need.

Each dataset updates monthly, typically in the first two weeks of the month. The data is comprehensive but requires a signed licence agreement on the upstream GOV.UK portal before downloads work — the MCP server will tell you clearly if that licence isn’t in place yet.

GOV.UK Guidance: Cutting Through the Complexity

Anyone who has spent time on GOV.UK knows it contains extraordinarily useful information buried inside extraordinarily dense writing. MCP servers with web access can retrieve and synthesise GOV.UK pages directly within Claude, which means instead of reading three guidance pages and trying to work out which one applies to your situation, you can describe your specific circumstances and ask Claude to tell you which rules apply and what you need to do.

I used this when navigating the employment status rules for a new contractor arrangement. Instead of reading four separate HMRC pages and two sets of guidance notes, I described the working arrangement to Claude with the GOV.UK MCP active and got a clear, structured answer that pointed me to the specific sections I actually needed. It saved about an hour.

Security and Safe Usage

The security concerns around MCP are real. In 2026, researchers identified malicious “shadow MCP servers” designed to steal credentials or inject hidden instructions into AI workflows.

My recommendation: Use reputable sources only. Start small. Read permissions carefully. Treat new integrations with the same caution you’d apply to any software connected to your business or personal data.

When used properly with trusted servers, the upside is substantial. A well-configured Claude setup can now research companies in minutes, summarise complex GOV.UK guidance, and dramatically reduce manual digital admin.