UK Contractor Finance: The Complete Guide

UK contractors are self-employed workers providing services to client businesses, typically on a project or day-rate basis. The financial structure used (Personal Service Company, umbrella company, or sole trader) shapes the tax position, take-home pay, and the operational requirements. IR35 status is the framing question that drives most of the tax outcome.

This guide covers the three main structures, the IR35 framework, the practical compliance for each route, and the financial planning specific to contractors.

The three contracting structures

Personal Service Company (PSC) - a limited company through which the contractor provides services. The contractor is typically the sole director and shareholder. Income comes through the company; the contractor extracts via salary and dividends. PSC suits engagements outside IR35 where genuine self-employment exists.

Umbrella company - a third-party PAYE provider that employs the contractor and handles all tax and NI deductions. The contractor invoices the agency or client through the umbrella; the umbrella pays them as an employee after deductions. Simpler administratively, more expensive on tax. Required for many inside-IR35 engagements where the client refuses to operate PAYE directly.

Sole trader - the contractor operates as a self-employed individual without a company. Most client businesses prefer not to engage sole traders for contracting work because of liability concerns and HMRC's deemed-employment rules; sole trader is rare in mainstream IT contracting but used in some sectors (creative freelancing, consulting).

Worked example: a software developer on GBP 600/day contract. Outside IR35: PSC route is typical. Inside IR35: umbrella is typical. Same day rate, very different take-home: outside-IR35 PSC delivers around GBP 100,000+ post-tax annually; inside-IR35 umbrella around GBP 75,000-80,000 due to higher tax burden.

IR35: Chapter 8 and Chapter 10

IR35 is the framework that determines whether a contractor providing services through an intermediary (PSC, partnership, individual) should be treated as if they were directly employed for tax purposes. Where IR35 applies (the engagement is 'inside IR35'), the engagement attracts PAYE and NI as if the contractor were employed.

Chapter 8 ITEPA 2003 (the original IR35) puts the determination obligation on the contractor's intermediary - the PSC. The PSC decides status, applies PAYE-style deductions where inside IR35. Chapter 8 still applies for engagements with small private-sector clients.

Chapter 10 ITEPA 2003 (off-payroll working) moved the determination obligation to the end client for public sector engagements from April 2017 and for medium/large private sector clients from April 2021. The client issues a Status Determination Statement (SDS) before engagement. Where inside IR35, the fee-payer (typically the agency or the client) applies PAYE deductions.

The factual tests under IR35 examine: right of substitution (can the contractor send a substitute?), control (does the client control how, when, where the work is done?), mutuality of obligation (is there continuing obligation between engagements?). These are the same tests as for general employment status under common law cases (Ready Mixed Concrete v Minister of Pensions, Hall v Lorimer).

PSC operation: corporation tax, dividends, salary

The PSC charges the client (or agency) for services. Income flows into the company. Allowable business expenses (necessary professional fees, equipment, business travel) are deducted. Corporation tax is paid on the remaining profit at 19% (up to GBP 50,000) or 25% (above GBP 250,000) with marginal relief in between.

The contractor as director-shareholder extracts the post-CT profit through salary and dividends. Typical pattern: salary up to the Personal Allowance (GBP 12,570) to use the PA and build NI credits, plus dividends from post-CT profit. Dividends tax: GBP 500 allowance, then 8.75%/33.75%/39.35% at the contractor's marginal band.

Worked example: a PSC contractor on GBP 600/day outside IR35, working 215 days a year = GBP 129,000 of fees. Allowable expenses (laptop, professional fees, business travel) GBP 8,000. Post-expenses profit GBP 121,000. Corporation tax GBP 25,500 (19% on first GBP 50k + 25% on next with marginal relief, around GBP 25,500). Post-CT GBP 95,500. Salary GBP 12,570 - no PA available for dividend, so all dividend taxed in basic+higher rate. Extract GBP 95,500 as dividend: GBP 500 allowance, GBP 37,200 at 8.75% (basic rate within stacking), GBP 57,800 at 33.75% (higher rate). Dividend tax GBP 22,759. Total take-home around GBP 85,000 net of all tax and NI.

Pension contributions through the company are typically tax-efficient. An employer pension contribution is deductible by the company at corporation tax rate (saving GBP 19,000 if GBP 100,000 contribution at 19% CT) and not taxable to the director. The annual allowance of GBP 60,000 applies.

Umbrella company operation

The umbrella employs the contractor under a contract of employment. The agency or client pays the umbrella the contract rate. The umbrella deducts the contractor's tax, NI, holiday pay accrual, Apprenticeship Levy (where the umbrella exceeds the GBP 3m payroll threshold, which most do), and the umbrella's margin (typically GBP 15-35/week or 5-7%).

Take-home is typically 60-65% of the agency rate. The deductions are similar in absolute terms to a permanent employee on the same gross, but the contractor sees a higher 'headline' rate that gets eaten by employer NI, Apprenticeship Levy, holiday pay accrual and the umbrella margin.

Holiday pay accrual is 12.07% of taxable pay (5.6 weeks out of 46.4 working weeks). Umbrella holds the accrual and pays it out when the contractor takes holiday or at engagement end. Some umbrella products 'roll up' holiday pay into the weekly amount; others hold it back.

Worked example: an inside-IR35 contractor on GBP 500/day through umbrella. Weekly invoice (5 days) GBP 2,500. Employer NI on the GBP 2,500 around GBP 320, Apprenticeship Levy around GBP 12, umbrella margin GBP 25. Taxable pay around GBP 2,143. Holiday accrual 12.07% = GBP 258. Net pay after employee tax + NI on around GBP 1,885 of cash pay: around GBP 1,360. Annualised take-home from this GBP 500/day rate: around GBP 65,000.

Choosing between PSC and umbrella

The decision typically follows the IR35 status: outside IR35 favours PSC, inside IR35 typically forces umbrella. Some clients refuse PSC engagements entirely (preferring umbrella for risk simplicity), removing the choice. Some agencies offer both routes.

For outside-IR35 engagements, PSC delivers materially better take-home through dividend efficiency. The administration burden (accountancy, Companies House filings, monthly bookkeeping) costs around GBP 1,500-3,000 a year - typically a fraction of the tax saving.

For inside-IR35 engagements, the PSC's dividend efficiency disappears (the deemed-employment treatment removes the dividend route). Umbrella is then operationally simpler with no material take-home difference. Many inside-IR35 contractors operate exclusively through umbrella for the engagement period.

Practical action: where a contractor has a mix of inside and outside IR35 engagements, maintaining a PSC for outside work and using umbrella for inside work is the most efficient. Some contractors keep the PSC dormant during inside-IR35 periods and reactivate for outside-IR35 work.

VAT registration for contractors

VAT registration is mandatory above GBP 90,000 of turnover in any rolling 12-month period (threshold from 1 April 2024). Most full-time PSC contractors hit this threshold easily on a day rate above around GBP 400.

The Flat Rate Scheme can simplify VAT. The contractor pays a flat percentage (varies by industry, 14.5% for IT consultants, 12-13% for other professional services) of gross turnover as VAT, instead of the standard input/output calculation. Where input VAT is low (typical for service contractors), Flat Rate often produces a small net positive versus standard accounting.

The 'limited cost trader' modification to Flat Rate (from April 2017) increases the flat rate to 16.5% for businesses with low VAT-able expense. The change reduced the Flat Rate advantage for typical PSC contractors; many migrated to standard VAT accounting after the change.

Worked example: a PSC contractor with GBP 120,000 of turnover (excluding VAT) charges clients GBP 144,000 including VAT at 20%. Under standard VAT, the contractor pays GBP 24,000 to HMRC less any input VAT (typically GBP 200-1,000 a year for a service business), netting around GBP 23,000-23,800 of VAT to HMRC. Under Flat Rate Limited Cost Trader 16.5%, the contractor pays 16.5% of GBP 144,000 = GBP 23,760 - similar in net effect.

Pension and retirement planning

Pension contributions through a PSC are highly tax-efficient. The company pays the pension contribution as a deductible business expense, saving corporation tax. The director receives the contribution into their pension tax-deferred, with no income tax or NI on the receipt.

Annual allowance GBP 60,000 (raised from GBP 40,000 in April 2023). Tapered allowance applies where adjusted income exceeds GBP 260,000, reducing to a minimum of GBP 10,000 above GBP 360,000+. Carry-forward of unused allowance from prior 3 years available under section 228A Finance Act 2004.

For a higher-rate PSC contractor, a GBP 40,000 employer pension contribution saves around GBP 32,000 of total tax (CT saving GBP 7,600 + dividend tax avoided GBP 13,500 + NI not applied + future tax-free growth in the pension). The contribution is the largest single tax-efficiency lever in the PSC structure.

Practical action: maximising the pension contribution each year (within annual allowance and considering the carry-forward) is the standard tax planning. Some contractors target GBP 40,000-60,000 per year contributions throughout their contracting career.

Insurance and protection

Contractors lack employee protections (statutory sick pay, redundancy pay, employer pension). The replacements come through personal insurance: income protection, critical illness, life cover, professional indemnity insurance.

Income protection at typical rates of GBP 30-100/month provides 50-65% of pre-illness income after a 3-month deferred period. Critical illness at GBP 30-80/month provides a lump-sum payment on diagnosis of listed serious conditions. Life cover at GBP 10-50/month provides protection for family.

Professional indemnity insurance is typically required by clients (some contracts mandate GBP 1m-5m of cover). Premiums vary by industry; IT contractors typically pay GBP 200-600 a year for GBP 1m cover. Public liability and employers liability (where the PSC has employees beyond the director) are similarly modest.

All these insurances can be paid by the PSC as a deductible business expense provided they relate to the business (PI, public liability are clearly business). Personal income protection and life cover are normally personal expenses paid from post-tax income, though some specific 'relevant life' policies for directors can be paid by the company under specific structures.

Setting up the PSC from scratch

Company formation through Companies House is online and typically completes within 24 hours. The formation fee is GBP 12 for the standard same-day online service. Some incorporation agents provide additional services (registered office address, model articles, share certificates) for GBP 50-150.

Required information: company name (must be unique and meet Companies House naming rules), registered office address (can be the director's home or an incorporation agent's address), at least one director (the contractor), at least one shareholder (typically the contractor), the share capital structure (typically 100 GBP 1 ordinary shares), and the standard model articles of association.

After formation, the contractor opens a business bank account. Fintech business banks (Tide, Starling, Mettle) typically open within 1-2 days; high-street business accounts can take 1-3 weeks. The bank account must be in the company name; personal accounts cannot be used for company transactions.

Practical action: most contractor accountancy firms (SJD, ClearSky, Crunch, Brookson) offer 'all-in-one' setup packages including company formation, accountant onboarding, business banking introduction, and initial VAT registration if applicable. Cost typically GBP 100-300 for the setup, then monthly accountancy fees from GBP 100-250.

Frequently asked questions

What's the difference between PSC and umbrella?

PSC is a limited company through which the contractor provides services; the contractor is director-shareholder and extracts income through salary and dividends after corporation tax. Umbrella is a third-party PAYE provider that employs the contractor and handles all deductions; the contractor receives net pay similar to a permanent employee. PSC suits outside-IR35 engagements (better take-home); umbrella suits inside-IR35 engagements (simpler, no dividend efficiency lost).

How does IR35 affect my tax?

IR35 determines whether the engagement is treated as deemed employment for tax. Inside IR35: PAYE and NI deductions apply as if directly employed; dividend efficiency through PSC is lost. Outside IR35: PSC structure with salary + dividends works normally. The chapter 10 off-payroll rules from April 2017 (public) / April 2021 (medium-large private) put the determination obligation on the client; chapter 8 still applies for small private-sector clients.

Should I register my PSC for VAT?

Mandatory above GBP 90,000 of turnover in any rolling 12-month period. Most full-time PSC contractors hit this on day rates above around GBP 400. Below the threshold, voluntary registration is possible but rarely advantageous. The Flat Rate Scheme (with the 16.5% limited cost trader rate) is similar to standard VAT for most service contractors; most use standard accounting now.

How much pension can I contribute through my PSC?

Up to the annual allowance of GBP 60,000 (2026/27). The company contribution is deductible at corporation tax rate (19-25%); the director receives the contribution tax-deferred in their pension. For a higher-rate contractor a GBP 40,000 contribution saves around GBP 32,000 of total tax versus extracting the same amount through dividends. Carry-forward of unused allowance from prior 3 years is available under section 228A Finance Act 2004.

Do contractors get Statutory Sick Pay?

No through a PSC structure (the contractor is a director-shareholder, not technically an employee for SSP purposes; even where treated as employee, SSP would come from the company itself - essentially the contractor paying themselves). Umbrella contractors are employees of the umbrella and qualify for SSP through that employment. Income protection insurance is the standard alternative for PSC contractors, typically GBP 30-100/month for 50-65% income replacement after a 3-month deferred period.

What insurances do contractors need?

Professional indemnity insurance (typically required by clients, GBP 200-600 a year for GBP 1m cover), public liability (modest cost, may be required by clients), income protection (GBP 30-100/month for 50-65% replacement), critical illness (GBP 30-80/month for lump sum on diagnosis), life cover (modest cost for family protection). Most PI, PL and some others are deductible by the PSC; income protection and life cover typically personal expense unless structured as relevant life cover.