Accountants for Contractors in London
Contracting in London offers exceptional financial opportunity but it also brings a level of financial and tax complexity that most generalist accountants are not equipped to handle. From managing your IR35 status and limited company accounts to structuring your director salary and dividends, filing quarterly VAT returns, claiming your full range of allowable expenses, and preparing for Making Tax Digital the demands on a London contractor’s financial management are continuous and highly technical.
At AccFirm, we provide specialist accounting for contractors across London from IT contractors and engineers to consultants, locums, construction professionals, and financial services contractors. You are assigned a single dedicated accountant with specific expertise in contractor taxation, IR35 compliance, and limited company management. All services are delivered under a fixed monthly fee with no hourly rates, no hidden charges, and no year-end surprises.
Whether you are setting up your limited company for the first time, need an IR35 review on a new contract, want to optimise your salary and dividend structure, or need comprehensive year-round accounting and tax support, AccFirm provides the expertise, the proactive advice, and the clear communication that London contractors deserve. Our team holds ACA, ACCA, ATT, and AAT qualifications and is authorised to act as your HMRC agent so you never deal with HMRC directly.
What Our Clients Say About AccFirm
Many of our Customers have started their early careers with AccFirm
We’ve been working with this accounting team for over two years, and the difference has been incredible. From bookkeeping and VAT returns to corporation tax planning, everything is handled efficiently and on time. They keep us fully compliant with HMRC while helping us improve cash flow and profitability. I highly recommend their services to any business owner.
Sarah Thompson
Thompson Retail Ltd
As a contractor under the Construction Industry Scheme (CIS), I needed accountants who truly understand HMRC requirements. They managed my CIS registration, monthly returns, and self-assessment without any stress. Their guidance saved me both time and money. Professional, reliable, and always available when needed
James Patel
Self-Employed Contractor (CIS)
AccFirm took over our accounts when our previous firm kept missing deadlines. Within three months they had identified over £4,200 in tax savings we had been leaving on the table including expenses we had never been told we could claim. They handle everything from our quarterly VAT returns to our year-end accounts and payroll, and our dedicated accountant is always reachable. For any London small business owner, I cannot recommend them enough.
Daniel Okonkwo
Okonkwo Facilities Management Ltd
MTD Ready
Revenue Increase
Client Satisfaction
Why London Contractors Need a Specialist Accountant?
IR35 is the single biggest financial risk facing London contractors today. Getting your status wrong or having a generalist accountant who does not understand the off-payroll working rules advise you incorrectly can result in HMRC issuing a tax demand covering years of back taxes, National Insurance, and penalties. HMRC actively investigates contractor arrangements and uses sophisticated data matching to identify potential non-compliance. The risks are real, and the cost of poor advice can be catastrophic.
Beyond IR35, the financial structure of your contracting business matters enormously to your take-home pay. The optimal split between director salary and dividends changes every year as tax rates and allowances are updated. A specialist contractor accountant reviews your position annually, ensures your structure is always optimal, and identifies every legitimate expense and relief available to you from travel and subsistence to home office costs, professional subscriptions, and equipment purchases.
AccFirm London contractor clients benefit from a dedicated accountant with deep expertise in all aspects of contractor taxation IR35 reviews, limited company management, salary and dividend optimisation, VAT, and Making Tax Digital compliance. We are not a generalist accounting firm that happens to serve a few contractors. Contractor accounting is a core specialisation, and every client receives advice that reflects that depth of expertise.
“Need Professional Business Support?”
Let our experienced accountants handle the compliance and financial complexities while you focus on growing your business.
Why London Contractors Choose AccFirm?
London contractors operate in one of the most financially complex environments in the UK. Day rates in the City and Canary Wharf are among the highest in the country but so are the HMRC scrutiny levels, the IR35 compliance demands, and the regulatory requirements that come with operating through a limited company. What London contractors need is not just an accountant who can file a tax return. They need a specialist who understands the entire contractor tax landscape from IR35 status assessments and off-payroll working rules to dividend optimisation, expense management, and Making Tax Digital compliance.
AccFirm works with contractors across London major contracting sectors IT and technology, engineering, financial services, management consulting, healthcare and locum work, construction and CIS, media and creative. Our team understands the specific financial challenges of each sector and provides advice tailored to your type of work, your contract structure, and your income patterns.
Every AccFirm contractor client is assigned a dedicated, qualified accountant not a call centre, not a rotating team, not an automated system. Your accountant responds to your queries the same day, reviews your contracts when you send them, and provides proactive advice on your tax position throughout the year. This personal, expert service at a competitive fixed monthly fee is why London contractors consistently recommend AccFirm.
Our Accounting Services for Contractors in London
AccFirm provides a complete accounting and tax service tailored specifically to contractors operating through limited companies and as sole traders across London. All services are available under a fixed monthly package.
IR35 Reviews & Advisory
IR35 is the most important piece of legislation affecting UK contractors. AccFirm provides professional IR35 contract reviews assessing your contract terms and working practices against HMRC’s criteria, advising on your status, and identifying any changes needed to protect your outside-IR35 position. For contracts that fall inside IR35, we advise on your options, calculate your deemed payment, and ensure all HMRC obligations are met correctly. We also assist with CEST tool assessments and Status Determination Statements for medium and large-client engagements.
Limited Company Formation & HMRC Registration
Setting up your contractor limited company correctly from the start is critical. AccFirm manages the complete Companies House incorporation choosing the right share structure, registering your company name, and completing all HMRC registrations for Corporation Tax, PAYE, VAT, and Self-Assessment. We advise on whether to operate as a limited company or sole trader based on your expected income, your IR35 exposure, and your growth plans. Most limited companies are fully set up and active within 48 hours.
Director Salary & Dividend Optimisation
The most valuable tax planning service AccFirm provides to contractor clients is the annual review of your director salary and dividend structure. By setting your salary at the optimum level typically the National Insurance secondary threshold and taking remaining profit as dividends, most contractors save between £3,000 and £8,000 per year compared to taking all income as salary. AccFirm reviews this structure every tax year, adjusting for changes in Corporation Tax rates, dividend allowances, and National Insurance thresholds to ensure your structure remains optimal.
VAT Returns & Making Tax Digital
Most contractor limited companies need to register for VAT once turnover exceeds £90,000. AccFirm manages your VAT registration, advises on the most appropriate scheme standard rate, flat rate, or annual accounting and handles all quarterly VAT returns and HMRC submissions. From April 2026, Making Tax Digital for Income Tax Self Assessment extends digital record-keeping requirements to self-employed individuals earning above £50,000. AccFirm ensures every contractor client is fully MTD-compliant from day one.
CIS Contractor Accounting
Contractors working in the Construction Industry Scheme (CIS) face specific compliance requirements CIS registration, monthly CIS returns, subcontractor payment management, and deduction records. AccFirm provides a dedicated CIS accounting service covering full monthly compliance, deduction tracking, and the annual reclaim of over-deducted CIS tax through Self-Assessment or Corporation Tax. Our team understands the specific challenges of CIS contracting including the irregular payment patterns and multiple client arrangements that make bookkeeping particularly complex.
Bookkeeping & Cloud Accounting
Accurate monthly bookkeeping is the foundation of every well-managed contractor limited company. AccFirm maintains your financial records using Xero, QuickBooks, or FreeAgent connecting your bank feeds, categorising all income and expenditure, reconciling your accounts monthly, and providing you with a real-time view of your financial position. We manage your expenses, ensure your contractor invoices are correctly recorded, and prepare management accounts to give you clear visibility of your profitability throughout the year.
“Need Professional Business Support?”
Let our experienced accountants handle the compliance and financial complexities while you focus on growing your business.
Our Step-by-Step Process for London Contractors
AccFirm contractor client goes through the same structured onboarding ensuring your limited company is correctly set up, your IR35 position is assessed, your accounts are configured for maximum efficiency, and your tax planning begins from day one.
Free Initial Consultation
We start with a no-obligation conversation to understand your contracting situation your sector, your current or planned contract, your IR35 position, your existing company structure (if any), and your accounting setup. This can take place by phone, video call, or in person at our London office. There is no commitment and no time pressure.
Fixed-Fee Proposal & IR35 Assessment
Within 24 hours, we provide a written proposal with a fixed monthly fee covering all agreed services. If you have an active contract that requires an IR35 review, we conduct a preliminary assessment and advise on any urgent actions needed. All fees are agreed in writing no hourly rates, no hidden charges.
Limited Company Setup or Transfer
If you are setting up a new limited company, we complete the Companies House incorporation and all HMRC registrations within 48 hours. If you are switching from another accountant, we contact your previous firm, obtain all records, and complete the HMRC agent authorisation transfer. Most contractor clients are fully set up and operational within five working days.
Cloud Accounting & Expense Setup
We configure your cloud accounting software Xero, QuickBooks, or FreeAgent connect your bank feeds, set up your contractor invoice templates, and establish your expense categories correctly. We walk you through how to use the system for maximum efficiency, including receipt capture via Dext for paperless expense management.
Ongoing Compliance & Proactive Tax Advice
Your dedicated AccFirm accountant manages all your ongoing compliance monthly bookkeeping, quarterly VAT returns, payroll, corporation tax planning, and annual accounts. We also review your IR35 position each time you start a new contract and advise on any structural changes needed. We are available year-round by email, phone, or video call.
Annual Tax Review & Take-Home Optimisation
At the end of each tax year, we review your entire financial position salary and dividend structure, expenses claimed, pension contributions, Corporation Tax position, and next year's planning opportunities. We file your year-end accounts, Corporation Tax return, and director's Self-Assessment, and provide a forward-looking tax plan for the coming year.
Tax Advice and Planning for London Contractors
For a contractor operating through a limited company in London, tax planning is not a once-a-year exercise; it is an ongoing, proactive discipline that runs through every invoice, every expense, and every business decision. The difference between a well-structured contractor and a poorly advised one can easily amount to £5,000–£10,000 per year in unnecessary tax. AccFirm ensures you are always in the well-advised category.
The single most impactful tax planning action for most contractor limited companies is the annual review and optimisation of the director salary and dividend split. As the table above shows, taking a salary at the National Insurance secondary threshold (£9,100 for 2025/26) and receiving the remainder of your income as dividends can save a typical London contractor £4,000–£8,000 per year compared to taking all income as salary. AccFirm reviews this structure every April when the new tax year begins.
Beyond salary and dividend optimisation, AccFirm’s contractor tax planning covers pension contributions through your company (a highly efficient way to reduce Corporation Tax while building long-term wealth), the maximisation of all allowable expenses, R&D Tax Credits for qualifying IT and engineering contractors, and Business Asset Disposal Relief planning for the eventual closure or sale of your contracting company.
“Need Professional Business Support?”
Let our experienced accountants handle the compliance and financial complexities while you focus on growing your business.
Tax Advice and Planning
Managing your tax position as a London contractor requires expertise that goes well beyond the annual Corporation Tax return. Every contract you take, every expense you incur, and every payment you draw from your company has tax implications and getting any of these decisions wrong can result in HMRC investigations, penalties, or years of backdated tax liability. AccFirm ensures that every aspect of your contractor tax position is managed correctly, proactively, and in your best financial interest.
Our contractor tax advisers stay fully up to date with every HMRC development, Finance Act change, and IR35 rule amendment that affects London contractors. When HMRC introduced the off-payroll working reforms to the private sector in April 2021, every AccFirm contractor client was briefed well in advance, their contracts were reviewed, and their structures were adjusted where necessary before the changes took effect, not after. That proactive approach is what distinguishes AccFirm from accountants who simply file what you send them.
From Making Tax Digital for ITSA which from April 2026 will require self-employed individuals and contractors earning above £50,000 to submit quarterly digital updates to HMRC to changes in Corporation Tax rates, dividend allowances, and National Insurance thresholds, AccFirm ensures every London contractor client is always prepared, always compliant, and always paying only the minimum tax legally required. Proactive tax planning is not a premium add-on at AccFirm it is part of every contractor client relationship.
AccFirm Contractor Accounting Process
Every AccFirm contractor client goes through the same structured onboarding ensuring your limited company is correctly set up, your IR35 position is assessed, your accounts are configured for maximum efficiency, and your tax planning begins from day one.
IR35 & Tax Position Assessment
We begin every new contractor-client relationship with a comprehensive review of your current position, your company structure, your active contracts, your IR35 status, your current salary and dividend arrangements, and your tax history. This assessment identifies any immediate risks, any tax savings available in the current year, and the optimal accounting structure for your specific contracting situation. Many contractor clients discover significant savings in the first review that their previous accountant had never identified.
Switching Contractor Accountant is Simple
If you are currently with another accountant or with one of the large online contractor accounting firms switching to AccFirm is completely straightforward and we manage the entire process. We contact your current accountant, request all outstanding records, accounts, and HMRC correspondence, and complete the agent authorisation transfer with HMRC and Companies House. If your previous accountant has missed filings, made errors in your accounts, or given you incorrect IR35 advice, we identify and resolve all issues as part of the transition.
Accounting Softwares
Get Specialist Contractor Accounting Support in London Today
Whether you are setting up your first limited company, switching from a large online accountancy firm, or need an urgent IR35 review on a new contract, AccFirm dedicated London contractor accountants are ready to help. We provide expert, proactive support at a fixed monthly fee that is transparent from day one.
Contact us today for a free, no-obligation consultation. We will review your current position, identify any immediate opportunities or risks, and provide a clear quote based on your specific contracting requirements with no sales pressure and no commitment required.
FAQs About Accountants for Contractors in London
How much does a contractor accountant cost in London?
Contractor accountant fees in London vary depending on the services included. Basic packages covering annual accounts and Corporation Tax only start from around £50 per month. Full-service packages covering bookkeeping, VAT, payroll, Self-Assessment, IR35 reviews, and ongoing tax advice typically cost between £80 and £150 per month. AccFirm charges fixed monthly fees with all agreed services included no hourly rates, no call charges, and no additional fees for IR35 reviews. Our packages for contractor clients start from approximately £80 per month. Contact us for a free, tailored quote based on your specific requirements.
Do I need a limited company to work as a contractor in London?
There is no legal requirement to operate through a limited company as a contractor you can work as a sole trader or through an umbrella company. However, for contractors earning above approximately £30,000 to £35,000 per year in profit, a limited company is typically the most tax-efficient structure allowing you to split income between salary and dividends, claim a wider range of business expenses, and significantly reduce your Income Tax and National Insurance liability. AccFirm advises every new contractor client on the optimal structure for their specific income level, IR35 exposure, and long-term plans.
What is IR35 and how does it affect London contractors?
IR35 (the off-payroll working rules) is tax legislation designed to identify contractors who are working in a way that is effectively equivalent to employment using a limited company as a vehicle to reduce tax. If HMRC determines that a contractor’s engagement falls inside IR35, the contractor is taxed similarly to an employee meaning Income Tax and National Insurance are deducted at source, and most limited company expenses cannot be claimed. The financial impact is significant: a typical London IT contractor earning £500 per day pays around £20,000–£30,000 more tax inside IR35 than outside. AccFirm provides professional IR35 contract reviews to protect your outside-IR35 status and manage your position correctly if you do work inside IR35.
What expenses can I claim through my contractor limited company?
The range of allowable expenses for contractors outside IR35 is extensive including travel and subsistence to temporary workplaces, home office costs, equipment and technology, professional subscriptions, accountancy fees, insurance, training and development, and marketing. AccFirm reviews your full expense profile to ensure every legitimate claim is identified and correctly categorised. Contractors working inside IR35 have significantly fewer allowable expenses AccFirm advises on this specifically when reviewing contracts that carry inside-IR35 risk.
How does salary and dividend optimisation work for contractors?
As a director of your contractor limited company, you have flexibility in how you extract income from your company. The most tax-efficient approach is typically to pay yourself a salary at or just above the National Insurance Lower Earnings Limit (currently £6,396 per year) or up to the NI Secondary Threshold (£9,100 per year) maintaining your state pension entitlement without triggering National Insurance contributions and then take the remainder of your required income as dividends from company profit after Corporation Tax. Dividends are taxed at lower rates (8.75% at basic rate) than salary income. AccFirm reviews and optimises this structure every April to ensure it remains optimal as tax rates change.
What is Making Tax Digital and how does it affect contractors?
Making Tax Digital for Income Tax Self Assessment (MTD for ITSA) will require self-employed individuals and contractors with total income above £50,000 to maintain digital financial records and submit quarterly updates to HMRC in addition to their annual tax return using HMRC-approved software. This becomes mandatory from April 2026. For most London contractor limited company directors, this affects their personal Self-Assessment rather than their company (companies are subject to separate requirements). AccFirm ensures every contractor client is fully MTD-compliant from the start of the 2026/27 tax year at no additional cost.
Can AccFirm help if I have missed previous contractor accounts filings?
Yes. AccFirm regularly works with contractors who have missed Corporation Tax returns, Self-Assessment deadlines, Companies House confirmation statements, or VAT return submissions. We file all outstanding returns, calculate the correct tax and penalties due, and negotiate with HMRC directly on your behalf for any penalty reductions where applicable. Acting promptly is always in your best interest the longer outstanding filings are left, the higher the accumulated penalties become. Contact us for a free, no-obligation review of your outstanding obligations.
Does AccFirm work with all types of contractors in London?
AccFirm works with contractors across all of London’s major contracting sectors IT and technology (software developers, project managers, business analysts, infrastructure engineers), financial services (investment banking, asset management, insurance), management consulting, engineering, healthcare and locum work, construction and CIS contracting, creative and media, and legal. Each sector has specific tax rules, expense profiles, and IR35 considerations. AccFirm team has experience across all of these sectors and provides advice that reflects the specific nuances of your type of contracting work.