Status Determination Statements

1. What an SDS Is

A Status Determination Statement is the formal, written IR35 decision an end-client makes about an engagement that runs through a personal-service company or similar intermediary. It states whether the engagement is inside or outside IR35, and gives the reasons. Since the April 2021 private-sector off-payroll reforms, the SDS is the document that everything else in the chain depends on, agencies, fee-payers, and contractors all act on the basis of what it says.

An engagement without an SDS is not legally "undetermined". If a qualifying end-client fails to issue one, HMRC deems them the fee-payer and pushes the PAYE/NIC liability onto them directly. The SDS is therefore as much a protection for the client as it is an obligation.

2. Who Must Issue One

The obligation falls on the end-client, the organisation that receives the worker's services, provided it meets the "medium or large" test. For the private sector this means the client exceeds at least two of: turnover over £10.2m, balance-sheet total over £5.1m, more than 50 employees. Public-sector clients are covered regardless of size.

Where the client is "small" under the Companies Act definition, the SDS obligation does not apply. The contractor's own limited company remains responsible for its own IR35 position under the original Chapter 8 rules. This is the "small company exemption" that many consultants and IT contractors rely on when working for scale-ups and owner-managed businesses.

3. What the SDS Must Contain

Three elements are mandatory for a statement to qualify as an SDS under ITEPA 2003 s61NA:

• A clear conclusion, the engagement is inside IR35, or it is outside IR35. "Probably outside, subject to review" is not a valid SDS.
• The reasons for the conclusion, a narrative explanation of the status tests considered (substitution, control, mutuality, financial risk, integration) and how the facts of this engagement applied to each.
• Evidence of reasonable care, a record of the inputs the client used: the contract, the role description, CEST output, legal opinion, standard-form role templates, and so on.

A single-line email that says "this role is outside IR35" is not an SDS, and HMRC has confirmed it will treat such statements as non-compliant. Most large employers now use a structured SDS template that names the client entity, the worker, the contracting PSC, the dates, the role title, the status conclusion, and an appendix listing the status-test reasoning.

4. Reasonable Care Test

The reasonable-care requirement is the single most enforced element of the SDS regime. An SDS that lacks reasonable care is treated as if it had never been issued, the client becomes the deemed fee-payer and the PAYE liability stays with them.

HMRC considers these signs of reasonable care: seeking the worker's own view on how the engagement operates, reviewing the actual contract terms, using a genuine status-assessment process (CEST, legal review, or internal panel) rather than a blanket determination across all contractors, keeping written evidence, and revisiting the determination if the role materially changes.

HMRC considers these signs of a failure of reasonable care: role-agnostic blanket determinations, using a standard template that does not engage with the specific facts, relying solely on a contract without considering day-to-day working practice, failing to respond to worker representations, and not re-reviewing when facts change.

5. Passing the SDS Down the Chain

The end-client must provide the SDS to both the worker and the party it contracts with (usually an agency). Every intermediary in the chain then has to pass the SDS on to the next party below it, until it reaches the deemed fee-payer, the party closest to the worker's PSC.

If any party fails to pass the SDS along, they become the deemed fee-payer themselves and inherit the PAYE and employer's NIC liability. This is why agencies now insist on receiving and forwarding SDSs in writing and keep audit trails, a missed forward in the chain can create a seven-figure liability on an agency that never set the rate.

6. The Client-Led Dispute Process

A contractor who disagrees with the SDS can trigger the client-led dispute resolution process. The contractor submits representations to the client, and the client must respond within 45 days with either a revised SDS or written reasons for maintaining the original determination.

There is no right of appeal to HMRC or to a tribunal under this process. The client has the final say on the SDS. A contractor's only further recourse is a personal self-assessment enquiry years later, by which point tax has already been deducted at source under PAYE.

Despite the limited remedy, the disputes process matters. Written representations force the client to document their reasonable-care position. If the client rejects the representations on weak grounds, their SDS is more vulnerable to challenge if HMRC later audits the engagement and finds the determination inconsistent with the evidence.

7. How Contractors Should Respond

• Request the SDS in writing before work begins. If the client has not issued one and the rules apply, flag it before the first invoice. Starting work without an SDS confuses the liability position and can cause payroll holds later.
• Read the reasoning carefully. A well-reasoned inside determination with defensible facts is different from a blanket determination. If the reasoning is weak, that is grounds for representations.
• Submit representations on the facts, not the conclusion. "I don't like the result" is ignored. "The SDS says I am controlled by the client, but my contract explicitly reserves the how-and-when, and in practice I worked from my own site with my own tools on four of six deliverables" has weight.
• Keep the full SDS pack for at least six years. HMRC can open an enquiry well after the engagement ends. The SDS, the contract, the representations, and the client's response are your primary defence evidence.
• Take the inside result seriously if facts line up. Fighting an inside SDS that is factually correct wastes time. Switch focus to restructuring the take-home via umbrella, salary sacrifice, and pension contributions.

If you've received an SDS you believe is wrong, our contractor accountancy service includes reviewing SDS determinations and drafting formal representations for the client-led dispute process.