[varispeed]

You say the consultancy “absolutely can substitute one worker with another.” In practice, clients regularly contract for named individuals, reject substitutes, and retain the same person for years. But it does not matter, because the substitution test is never applied to them. A one-person company in identical working conditions has to defend its right of substitution. A large firm placing a single named worker in the same arrangement is never asked the question.

Now the tax argument. Picture three people sitting next to each other doing the same job at the same client. One is employed directly on £70k. One works for a large consultancy, earns £60k, and has no idea the consultancy charges £2k a day for their labour. One runs their own company and charges £600 a day. The employee pays income tax and NI on £70k. The consultancy worker pays income tax and NI on £60k, while the consultancy captures the spread and, being a multinational, routes the margin offshore paying little or no UK tax. The small business owner pays themselves a salary, corporation tax on profits, and dividend tax on what they take out - and spends the margin locally.

From a pure tax yield perspective, the small business owner generates the most revenue for the Treasury and the most benefit for the local economy. The large consultancy generates the least. Yet the entire framing of IR35 is designed to make the two employed workers resent the business owner for “not paying their fair share,” while the consultancy quietly extracting the largest margin and contributing the least tax is never part of the conversation. Paying through dividends and salary is not avoidance, it is the normal mechanics of running a limited company, which exists precisely because PAYE was not designed for how independent businesses operate.

If a large consultancy places a single named worker at one client, on client equipment, during client hours, for four years, with no practical substitution ever exercised, why is that firm not subjected to the same deemed-employment assessment that a one-person company would be in identical circumstances? Because the legislation is scoped by ownership. It activates when the person doing the work also owns the business providing it. A worker who builds and runs their own company is treated as inherently suspect. A separate corporate entity extracting the same margin from the same labour is not.

If you think that framing is wrong, explain why the ownership trigger exists rather than a universal status test applied equally to all companies supplying labour. That is the question.

[scott_w]

> You say the consultancy “absolutely can substitute one worker with another.” In practice, clients regularly contract for named individuals, reject substitutes, and retain the same person for years. But it does not matter, because the substitution test is never applied to them. A one-person company in identical working conditions has to defend its right of substitution. A large firm placing a single named worker in the same arrangement is never asked the question.

It's a good thing that HMRC don't apply this as the only test then.

> From a pure tax yield perspective,

This is totally irrelevant to the discussion. In fact, the rest of this paragraph is irrelevant because it's just you going off on some rant you derived from a Communist Party pamphlet or something.

> Because the legislation is scoped by ownership.

Not only ownership, it's a mixture of factors. I've worked with other IT workers who fall outside the scope of IR35.

Plumbers and electricians fall outside the scope of IR35 in most situations, despite being single person limited companies. You say it's triggered by ownership structure, yet these businesses follow the same ownership structure without triggering IR35. If it's triggered by ownership structure and classism, how does this fit into your thesis?

> If you think that framing is wrong, explain why the ownership trigger exists rather than a universal status test applied equally to all companies supplying labour. That is the question.

I already did and so did you right here:

> Picture three people sitting next to each other doing the same job at the same client. One is employed directly on £70k. One works for a large consultancy, earns £60k, and has no idea the consultancy charges £2k a day for their labour. One runs their own company and charges £600 a day. The employee pays income tax and NI on £70k. The consultancy worker pays income tax and NI on £60k

These three situations create three completely different contracts, working structures and, thus, tax arrangements! It's wild how you seem to get it but your brain won't allow you to see the answer that's staring you in the face.

[varispeed]

The plumber example actually undermines your argument. Plumbers typically provide services to individuals, not businesses, which places them outside the scope of Chapter 10 entirely. They can self-declare as outside IR35. But if that same plumber were delivering services to a corporation meeting Chapter 10 criteria, the client would have to perform a status determination, and depending on their risk appetite they could absolutely deem that engagement as inside IR35 to cover their compliance exposure. IR35 has nothing to do with number of clients, type of trade, or whether you are a plumber or a software developer. Presenting plumbers as inherently outside IR35 by nature of their work is misleading.

You dismissed the tax yield comparison as "a Communist Party pamphlet." That is not a rebuttal. If the stated purpose of IR35 is protecting tax revenue, and the structure generating the most tax for the Treasury is the one being constrained while the structure generating the least is left untouched, then the policy is not achieving what it claims to achieve. You have not addressed this because you cannot. You say the three workers create "completely different contracts, working structures and tax arrangements" and that my "brain won't allow me to see the answer." The working structure is identical. The contracts differ because the law requires them to differ depending on who owns the supplying company. The tax arrangements follow from that. You keep pointing at the consequences of the policy and presenting them as the justification for it. That is circular reasoning.

You have repeatedly described how you think IR35 works, inaccurately in several places, while avoiding the question I am actually asking. I am not asking about the mechanics. I am asking about the design. Why does the deemed-employment test activate based on who owns the company supplying the labour, rather than being applied universally to all companies supplying labour in identical working conditions?

Resorting to personal attacks and dismissing inconvenient arguments as "rants" is not the same as answering the question.