The 40/60 Split: How to Share Profit With Your Contractors

The profit split is how some construction arbitrage operators pay subcontractors without locking in a fixed day rate. Instead of a set daily or per-job amount, the contractor receives a percentage of the profit on each job. A typical starting point is 60% to the contractor and 40% to the operator, with materials stripped out before the split is calculated.

How the profit split with contractors works in practice#

The mechanics are straightforward. The operator wins the job, quotes the client, and buys all materials. Materials come off the top before anything is divided. The contractor delivers the labour. Once the client pays, the profit - revenue minus materials and any direct costs agreed upfront - is split by the percentage agreed.

A worked example, using illustrative figures:

• Client pays £5,200 for a full bathroom installation
• Materials (tiles, fixtures, pipework, adhesives): £1,400, bought by the operator
• Margin available to split: £3,800
• Contractor receives 60%: £2,280
• Operator keeps 40%: £1,520

The operator's £1,520 then covers insurance, overhead, software, admin, and their own margin. It is not all take-home. But they earned it from a desk, not a toolbelt.

This model shows up regularly in construction arbitrage businesses that have moved past the early stage and have enough volume to make the percentages predictable. It keeps the contractor incentivised without the operator committing to a fixed cost before knowing what the job earns.

What counts as profit - and what does not#

This is where most operators cause problems the first time they set this up. "Profit" in the split model does not mean gross revenue. It means what is left after materials and agreed direct job costs are removed.

Materials are always excluded. The operator buys them directly - this keeps the VAT input credit in the right place and prevents any incentive for the contractor to inflate material costs. If the contractor starts buying materials and deducting them before the split, the numbers become unverifiable. Keep materials in the operator's name, every time.

Other costs that should be agreed upfront and stripped out before the split:

• Skip hire or specialist waste disposal tied to that specific job
• Equipment hire for that site (a specialist machine not in the contractor's standard kit)
• Access permits or parking costs tied directly to that site

What does NOT come off before the split:

• Insurance and public liability cover
• Office software and admin tools
• Phone and general overhead
• The operator's time spent managing the job

Those are fixed business costs. They are covered from the operator's 40%. If the operator tries to strip general overhead out before the split, they are effectively paying themselves twice and reducing the contractor's cut without a valid reason.

The test is simple: is this cost something that existed only because of this specific job, agreed with the contractor before work started? If yes, it can come off first. If no, it stays in the operator's overhead.

Why 60% to the contractor and 40% to the operator?#

The 60/40 split reflects who carries what on the job itself. The contractor shows up, applies a skilled trade, and takes physical responsibility for the work quality. The operator sourced the client, priced the job, bought materials, and holds the commercial risk if the client does not pay.

It is a starting point, not a fixed rule. Some operators run 50/50 when the contractor is also managing a small team on site. Some go 65/35 in the contractor's favour when the trade is highly specialist and the operator could not easily replace that person. The 40/60 is the right default when the operator provides all materials and handles everything client-facing.

For the model to hold long-term, both sides need to see the job price before work starts. A contractor going in blind on a job the operator has priced thin will feel shortchanged when the split produces a lower number than expected. Show the contractor the quote. It builds trust and removes a recurring source of friction.

Profit split vs day rate - when to use each#

Both models work. The choice is which fits the job.

Use a day rate when:

• The job scope is hard to define before starting
• The work is likely to run over or under in time
• You need the contractor for a fixed block of time and the outcome varies

Use a profit split when:

• The job is clearly scoped and priced before the contractor starts
• You want the contractor to have skin in the job's efficiency
• You are running a steady pipeline of similar jobs and the numbers are predictable

The day rate removes the contractor's incentive to be quick - they earn the same regardless of how long it takes. The profit split removes that problem. But it introduces a different one: if the job runs into trouble and the margin compresses, the contractor takes the hit alongside the operator. That is fair when the trouble came from the contractor's side. It is harder to justify when the job went thin because of the operator's original pricing.

Understanding what the spread looks like across your jobs is the foundation for choosing the right model. Once you know what a job type typically earns, you can decide whether the split or the day rate makes more sense for that work.

There is also a third option worth knowing: a fixed per-job price, agreed before the contractor starts. "I will pay you £900 to fit this bathroom." Clean, no percentages, no calculation after the fact. Experienced operators often move here once they know their contractors well and can price confidently. It is the simplest arrangement of the three - no disputes about what counts as profit, no after-the-fact settlement.

How the profit split interacts with CIS#

Under the Construction Industry Scheme, CIS applies to the labour element of what you pay subcontractors - not to materials. On a profit split arrangement, the amount the contractor receives after the calculation is treated as a labour payment for CIS purposes.

The deduction rates for 2026/27 are:

• 20% for registered subcontractors
• 30% for unregistered subcontractors
• 0% for those with gross payment status (approved by HMRC)

Verify each contractor's CIS status through the HMRC online service before the first payment and keep a record of every verification. File your monthly CIS returns on time - HMRC charges a £100 fixed penalty for late submission, and the penalties stack per month.

The profit split arrangement does not change the CIS rules. The only difference from a standard labour payment is that the labour amount is determined by the split calculation rather than a fixed agreed price. The CIS mechanics are otherwise identical.

For a full breakdown of how VAT works alongside the CIS in a contractor arbitrage business, including the domestic reverse charge on subcontractor invoices, see VAT and contractor arbitrage: what UK operators get wrong.

What can go wrong#

Three failure points, in the order I have seen them most often:

No written definition of profit. The operator says "we split the profit 60/40" and assumes the contractor understands what profit means in this context. They often do not. A one-page signed document defining exactly which costs come off before the split prevents a dispute on every job settlement.

The job runs thin and the contractor feels ambushed. If the operator priced the job badly and the margin is tight, the contractor expected a reasonable cut and gets a thin one. Showing the contractor the original quote before work starts deals with this. They know what they signed up for.

CIS errors. Forgetting to verify a contractor, applying the wrong deduction rate, or missing a monthly return. The cost lands on the operator. A simple checklist at the start of every new subcontractor relationship - verify status, note the rate, set a calendar reminder for the monthly return - prevents almost all of it.

Putting it in writing#

A basic profit split agreement does not need a solicitor. A one-page signed document covering:

1. How profit is defined (revenue minus which specific costs, written out)
2. The split percentage agreed
3. When and how the contractor is paid (usually on client payment, not job completion)
4. The contractor's CIS status and the deduction rate that will apply
5. What happens if the client does not pay or pays late

That last point is standard in UK construction - the contractor is typically paid only once the operator has received the client's payment. Make it explicit. It protects the operator's cash flow, but the contractor deserves to know it going in.

For a deeper look at how the money works across a construction arbitrage business - what margins are realistic, how much the model can earn, and how to structure the whole thing - contractorclub.vip has the practical detail on running and scaling it.

FAQ#

What is the profit split in construction arbitrage?

The profit split is an arrangement where the subcontractor is paid a percentage of the job profit rather than a fixed day rate. A typical split is 60% to the contractor and 40% to the operator, calculated after materials and any pre-agreed direct job costs have been removed from the total invoice.

What counts as profit in a profit split arrangement?

Profit in this context is revenue minus materials and any agreed direct job costs such as skip hire or specialist equipment. General overheads - insurance, software, admin - are not deducted before the split. They come out of the operator's 40%. Materials should always be bought by the operator so the VAT input credit stays in the right place and costs cannot be inflated.

What is the difference between a profit split and a day rate for subcontractors?

A day rate is a fixed daily payment regardless of what the job earns. A profit split ties the contractor's pay to the job's profitability. Day rates suit variable-scope or time-uncertain work; profit splits work better on clearly priced, well-scoped jobs where both sides benefit from efficiency. Many operators use both, matching the model to the job type.

How does the profit split interact with CIS deductions?

Under the Construction Industry Scheme, CIS deductions apply to the labour element of what you pay subcontractors. On a profit split, the amount the contractor receives after the split is treated as a labour payment. Deduct 20% from registered subcontractors, 30% from unregistered ones, and nothing from those with gross payment status. Always verify status with HMRC before the first payment.

Last checked: 28 September 2026.