IR35 contract checker for UK startups
Our advanced IR35 contract checker provides instant, comprehensive risk analysis. As a result, you’ll receive clear findings with actionable fixes within seconds.
- Your document is processed securely and never stored permanently.
How Our IR35 Contract Checker Works
Our IR35 contract checker analyzes your contractor agreement against HMRC’s key employment status tests in three simple steps.
1
Upload your contract
Drag and drop your PDF or DOCX contract. The IR35 contract checker securely processes your document without permanent storage.
2
Automated analysis
Within 60 seconds, our AI examines control, substitution, mutuality of obligation, and financial risk factors that determine IR35 status.
3
Instant risk report
Receive a clear report with color-coded findings, suggested clause rewrites, and practical next steps to reduce HMRC challenge exposure.
Moreover, the checker highlights which clauses drive risk so you can fix them before signing.
Upload Your Contract
Get your IR35 analysis in under 60 seconds
What the IR35 contract checker flags
IR35 looks at the working relationship, not just the wording. Our checker analyses the factors used by HMRC to decide employment status for tax.
Control
Who decides how, when and where the work is done. Strong client control points to “inside IR35”.
Substitution
Is there a genuine, unfettered right to send a suitably qualified substitute? Approval requirements carry less weight.
Mutuality of Obligation
Is the client obliged to offer work and contractor obliged to accept? Lack of ongoing obligation supports “outside IR35”.
Financial Risk
Who bears costs, provides equipment, and fixes defects at their own expense?
Integration
Multiple clients, marketing, professional insurances, and other indicators of independent business.
Business on Own Account
Who decides how, when and where the work is done. Strong client control points to “inside IR35”.
Consequently, your team can align faster and reduce HMRC challenge exposure.
When to Use an IR35 Contract Checker vs HMRC CEST
Understanding which tool to use helps you get the right guidance at the right time.
Use Our IR35 Contract Checker When:
- You're drafting or reviewing contractor agreements before signing
- You need specific clause-level feedback and rewrite suggestions
- You want to identify and fix risks proactively
- You need a shareable report for stakeholders or contractors
- You're comparing multiple contract templates
Use HMRC's CEST Tool When:
- You need HMRC's official determination for an existing engagement
- The working relationship is already established
- You're preparing a Status Determination Statement (SDS)
- You want HMRC's view based on actual working practices
- You need documentation for compliance purposes
Best practice: Use our IR35 contract checker during contract negotiation to fix issues early, then run HMRC’s CEST tool before the engagement starts to confirm your status determination.
IR35 Risk Indicators
Key factors that influence your IR35 status determination
Red Flags (Inside IR35)
- Client decides working hours, location and methods; approval needed for routine decisions
- No genuine right of substitution; individual named and required
- Ongoing obligation to offer/accept work; rolling tasks with no clear deliverables
- Paid by time with no delivery risk; client provides all equipment
- Managed like staff: line-managed, internal approvals, holiday cover
Green Flags (Outside IR35)
- Outcome-based project with milestones; you control how to deliver
- Genuine unfettered substitution right with contractor arranging substitute
- Ability to decline further work; discrete statements of work
- Fixed-price elements, own insurances, own equipment, multiple clients
- Minimal integration; no staff perks or employee-style benefits
Sample IR35 Analysis
See what your report will look like
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Suggested Improvements
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Add explicit wording: "Contractor has autonomy over how the Services are performed."
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Tighten substitution: remove "sole discretion" approval; keep reasonable vetting only.
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Add acceptance criteria and change-control to separate out future work.
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Include liability/insurance clauses (PI £1m) and equipment responsibility.
Disclaimer: This is an automated pre-assessment to help you spot risk. It is not tax or legal advice. Use alongside your client's SDS and professional advice where needed.
IR35 FAQs
Common questions about off-payroll working rules
What is IR35 / off-payroll working?
UK rules that determine whether a worker is employed or self-employed for tax when supplying services via an intermediary (e.g., a limited company).
Who decides my status?
Public sector & medium/large private sector: the client decides and must issue an SDS.
Small private-sector clients: the contractor decides.
Is your checker the same as HMRC’s CEST?
No. Our checker gives best-practice risk guidance and suggested wording. CEST is HMRC’s questionnaire producing HMRC’s view based on your answers (last updated 30 April 2025). Many users use both.
What’s the small-company exemption?
If the client is “small” (Companies Act thresholds), the contractor remains responsible for IR35. Check thresholds before the tax year; group structures matter.
Do you store my contracts?
No. Files are processed transiently for analysis and not stored permanently.
Can I rely on this report if HMRC investigates?
Use it as internal evidence of reasonable care and to improve contracts/practices. Always align the actual working practices with the contract and seek advice on edge cases.
Ready to Check Your IR35 Status?
Average time to first result: 20–60 seconds
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