Determining your IR35 status

As a contractor, freelancer or small business, it’s important to have an awareness and understanding of IR35 and how it’s determined to ensure that you are paying the correct amount of Tax and National Insurance.

How does IR35 impact me?

Your IR35 status (which can vary from contract to contract) determines your tax position with HMRC.  It’s important to understand the definition and your personal risk of being defined as a ‘disguised employee’ of your client for each contract you undertake. It’s also important to understand that IR35 runs across every business sector and specialism.

How is IR35 status determined?

HMRC have developed a tool called CEST – Check employment status for tax. You may find this service useful to understand how HMRC class whether an assignment is inside or outside IR35.

But be warned: it’s just a guide – whilst HMRC say they’ll stand by the results, it’s well known to be biased and the deck is unfairly loaded in HMRC’s favour. It has been proven to be unreliable and suggests contractors and consultants are inside IR35 when legal challenges have shown they’re not.

There are a lot of factors that are assessed to determine whether you are operating outside IR35 (a truly self-employed contractor) or inside IR35 (working as a disguised employee) and it can vary from contract to contract.  HMRC looks at the following areas when determining your status:

Is the contract a contract of service or a contract for services?

Your contract (or standard terms and conditions that you issue to the client or agency that you are working for) is a legally binding document and needs to define your relationship with the client/agency as well as outline your working practices and services that you are providing for the specific job. The core areas that need to be present in the contract to fall outside of IR35 are:

  1. Control – is should be explicit that you control how the work is completed and that you provide a service through your own methods.
  2. Substitution – there should be the opportunity to substitute yourself for another suitably qualified person, or sub-contract whilst retaining the control and risk associated with this.
  3. Mutuality of obligations – outlining the obligations of each company to ensure that there is no obligation for further work when the contract ends (as would be expected by an employee). The contract needs to state a clear end date or termination of the contract based on the completion of the project or delivery of the contracted outcome.
  4. The right of dismissal.  Notice periods are seen as indicative of employment by HMRC and so the client should have the right to terminate the contract immediately in the majority of circumstances, however some short notice periods can be defendable. If a contractor can’t terminate the notice period immediately, or has a notice period of longer than one month, they are deemed as working under IR35.

It is important to note that having a well-drafted set of terms and conditions of contract is not enough.  You need to demonstrate that the clauses are true to your working practices.

Working practices – do you act as an employee or a self-employed entity?

It is critical that you act and work as a separate entity to your client to fall outside of IR35.  Your working practices need to reflect that you have a business to business relationship with your client.  There are some core areas that you can address as part of your overall business set up:

  1. Provision of your own insurance.
  2. Non-exclusivity (you work with many clients at once or have ability to do so).
  3. You accept a certain amount of financial risk (this can be rectifying errors at your own expense).
  4. In business of own account – you can show that you are responsible for your success or failure as a business entity.
  5. Provision of your own training and equipment (to maintain standards, you are not penalised for training provided by a client if it is to familiarise yourself with their operations/procedures/equipment that is required by the specific task stated in the contract).
  6. Lack of employee benefits. It is important to ensure that you do not attract any employee benefits from the client.
  7. Intention to be self-employed. This is a culmination of the above and other softer measures such as having your own website, email addresses, advertising, trade marks for example.


You control how, where and when you perform the work and when you take time off.  If the client can stipulate your working hours, the place where you work, grant permission for time off and stipulate how you perform the tasks this could be deemed as you working as an employee.  It is also worth ensuring that you are contracted for specific names projects/tasks and that you do not perform alternative tasks to fill the allotted time as this would be deemed as working as an employee.

Financial risk

Fixed-price quotations for projects are favourable, as you control the level of risk.  You should also be able to exhibit that you are expected to correct (your own) errors without charging additional fees.

Employee benefits

Ensure that you do not accept the following: parking spaces, ID and security passes that don’t state you are a contractor/visitor, business cards, use of a subsidised staff canteen and other employee benefits.  You should ensure that you outline what remuneration and payment terms you will apply in the contract.

In business on own account

It’s important to show that you are in business for yourself and that you maintain and invest in your own company.  Simple every-day investments are all examples of this: business cards, websites and email addresses, marketing, company stationery, VAT registration, logos and trademarks, business phones, company credit cards, company business bank account, Professional Indemnity and other business insurance, professional training and development.  Can you also show additional revenue streams in addition to the contract in question? Do you have a financial business plan in place, with cash flow forecasts?


If you are required to provide your own equipment that is integral to the completion of the project, this is a good example of acting as a separate entity from the client.  This can include laptop, software (which the client doesn’t use), processes or methodology specific to your company.

Intention of parties

Does your contract with the client state your relationship as a contractor/service provider and that they are the client?  It is important that you perform your duties as a contractor/service provider servicing a client.  This can become more difficult if you are working with a client for a sustained period of time, or exclusively.  It is important to maintain the professional boundaries set out within the contract and within the IR35 guidance notes provided by HMRC.

Be prepared – evidence is the best defence

As with all dealings with regulatory and financial bodies, great record keeping and scrupulous collection of evidence is the best way to ensure that should your status come under scrutiny, you’ll have everything at your fingertips.  You’ll have a lot of the paperwork filed (as part of your accounts filing, but there are other supporting documents that will be useful in showing your independence and company status.

  • Insurance policies and schedules (keep the schedule for as many years as you can, but five as a minimum for your Professional Indemnity cover)
  • Business premises proof- lease or contract for premises and utility bills.
  • Contracts – for all engagements with clients, especially the long-standing relationships.
  • Efficiency gains – tenders and proposals for fixed-price job gains.
  • Proof of assistance – employee records, accounting records.
  • Marketing spend – receipts and briefs for the marketing undertaken. Copies of advertising and marketing materials.
  • Repair at own expense – contract clauses, details of mistakes rectified, details of costs incurred by you to rectify your mistakes.
  • Client risk – accounting records of write-offs, copies of correspondence with client involved, legal action records.
  • Business entity – receipts for production as well as copies of the materials such as websites, business stationery and branding such as trade mark applications.
  • Billing – invoices and correspondence related to payment terms.
  • Substitution – contact clauses, level of sign-off by the client, payment terms, audit trail of previous substitutes and subcontracting.
Next → Up next in this guide: Umbrella companies and IR35

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0800 033 7827

Calling from overseas

+441332 460 010

Head Office

1 Derwent Business Centre
Clarke Street