If your agency has claimed R&D tax credits on subcontractor costs, you might be in for an unwelcome surprise. The PAYE-NI cap on R&D claims restricts the amount of payable tax credit you can receive to the total PAYE and National Insurance your company paid in that period. For agencies that rely heavily on freelancers, contractors, or external developers, this cap can slash a legitimate claim to almost nothing.
I have seen it happen to a 15-person creative agency in Shoreditch. They had spent £180,000 on subcontractor developers building a proprietary analytics platform. Their R&D claim was strong, genuinely qualifying projects. But when HMRC applied the PAYE-NI cap, their payable credit dropped from £47,000 to just £4,200. The rest was lost. They had no idea the cap existed.
Let me explain exactly how this works, when it applies, and what you can do about it.
What Is the PAYE-NI Cap on R&D Claims?
The PAYE-NI cap was introduced in 2021 to prevent abuse of the R&D tax credit system. HMRC had seen companies claiming large payable credits based on subcontractor costs while paying almost no UK employment taxes themselves. The cap was designed to stop that.
Here is the rule in plain English. If your company is claiming under the SME R&D scheme and you are loss-making (so you want a payable tax credit rather than a reduction in corporation tax), the payable credit you receive is capped at the total of:
- Your company's Class 1 employer NI contributions for the period
- Your company's PAYE payments for the period
The cap applies to the payable element of the credit, the cash you get back from HMRC. If your company is profitable and using the R&D credit to reduce your corporation tax bill, the cap does not apply. That is an important distinction, and it catches a lot of agency founders out.
For the 2025/26 tax year, the SME payable credit rate is 10% of the surrenderable loss (down from 14.5% for pre-April 2024 claims). The cap calculation itself has not changed. You calculate the total PAYE and Class 1 employer NI you actually paid in the period, and that figure sets the maximum payable credit you can receive.
Why Agencies Get Caught Out
Agencies have a structural problem with this cap. Most agencies, particularly digital, creative, and web design agencies, operate with a core team of permanent staff and a much larger pool of freelancers and subcontractors. That is a standard agency model. But it creates a mismatch.
Your qualifying R&D expenditure includes:
- Staff costs (salaries, employer NI, pension contributions)
- Subcontractor costs (usually 65% of payments qualify, or 100% if the subcontractor is a connected party)
- Software and cloud costs used directly in the R&D
- Consumables and materials
If most of your R&D spend is on subcontractors, your qualifying costs are high. But your PAYE-NI cap is based only on your permanent staff costs. The two figures can be wildly different.
Take a typical example. A 12-person digital agency in Manchester Northern Quarter has 4 permanent developers and 8 regular freelancers. They spend £200,000 on subcontractor developers building a new AI-driven campaign tool. Their permanent staff costs generate £35,000 in total PAYE and employer NI for the year. Their R&D claim produces a payable credit of £52,000. The cap restricts it to £35,000. They lose £17,000 in cash they were expecting.
That is not a theoretical scenario. It happens every day.
When the Cap Does Not Apply
The cap only applies to the payable credit element of an SME R&D claim. If your agency is profitable and paying corporation tax, the R&D credit reduces your tax bill directly. There is no cap on that reduction. You simply deduct the enhanced expenditure from your profits and pay less tax.
So if your agency turns over £1.2m, has profits of £150,000, and qualifies for R&D relief of £80,000 in enhanced expenditure, your taxable profit drops to £70,000. Your corporation tax bill reduces from £37,500 to £17,500 (assuming the 25% rate). The cap does not touch that.
The cap only bites when you are loss-making and want HMRC to write you a cheque. That is usually early-stage agencies, agencies that have invested heavily in a specific project, or agencies that have had a bad year.
If you are claiming under the RDEC scheme (for large companies), the cap works differently. RDEC is treated as income and taxed, but the cap does not apply in the same way. Most agencies will be under the SME scheme unless they are part of a larger group.
How the Calculation Works
Let me walk through a real calculation so you can see the numbers.
Agency profile: A 10-person web design agency in Bristol Harbourside. Turnover £650,000. Loss-making because they invested £300,000 in a new proprietary CMS platform.
Qualifying R&D costs:
- Staff costs (3 permanent developers): £120,000
- Subcontractor costs (5 freelancers): £150,000 (65% qualifies = £97,500)
- Software licences: £12,000
- Total qualifying costs: £229,500
R&D calculation (SME scheme):
- Enhanced expenditure: £229,500 x 186% = £426,870
- Surrenderable loss: £426,870 (assuming no other income)
- Payable credit at 10%: £42,687
PAYE-NI cap calculation:
- Total PAYE paid on all staff: £28,400
- Total employer NI paid: £12,600
- Cap figure: £41,000
Result: Payable credit is capped at £41,000. The agency loses £1,687. Not catastrophic, but still money they had budgeted for.
Now change the subcontractor spend to £250,000 and keep everything else the same. The qualifying costs jump to £286,500. The enhanced expenditure becomes £532,890. The payable credit is £53,289. But the cap stays at £41,000. The agency loses £12,289.
That is the pattern. The more you spend on subcontractors relative to permanent staff, the more the cap bites.
What Counts Towards the Cap
Only PAYE and Class 1 employer NI paid in the period count towards the cap. That means:
- Salaries of all employees (not just those doing R&D)
- Employer NI on all employees
- PAYE on all payments, including bonuses and commissions
What does not count:
- Employee NI contributions (that is the employee's cost, not the company's)
- Pension contributions (these are not PAYE or NI)
- Class 1A NI on benefits in kind (that is separate)
- Apprenticeship levy
- Construction Industry Scheme deductions
Some agencies try to inflate their cap by paying directors larger salaries in the R&D period. That can work, but only if the salary is commercially justifiable. HMRC will challenge a sudden spike in director salary that has no business rationale. You cannot game the system by paying yourself £100,000 in March and then taking it back as a dividend in April. HMRC has seen that before.
Strategies to Manage the PAYE-NI Cap
If you know the cap is going to restrict your claim, you have options. None of them are perfect, but they can make a difference.
Bring Subcontractors In-House
If your R&D spend is heavily weighted toward freelancers, consider hiring them as employees for the duration of the project. Their salaries then generate PAYE and NI that feeds the cap. This only works if the freelancer is willing to become an employee, and you need to manage the IR35 implications carefully. But for a 12-month R&D project, it can transform your claim.
Use Connected Subcontractors
If you subcontract R&D work to a connected party (someone who controls your company or is controlled by it), 100% of the payment qualifies rather than 65%. But the connected party's PAYE and NI also count towards your cap. This is complex and needs proper structuring. Do not attempt it without professional advice.
Plan Your R&D Spend Across Multiple Periods
If your R&D project spans two accounting periods, you can smooth the subcontractor spend so it does not concentrate in a single period where the cap is tight. This is basic tax planning, but many agencies do not think about it until the claim is submitted.
Consider the RDEC Scheme
If your agency is large enough (over 500 employees or turnover over £100m and balance sheet over £86m), you may be forced into the RDEC scheme. The cap does not apply in the same way. But RDEC is generally less generous for loss-making companies, so this is rarely a positive move.
Accept the Cap and Plan Cash Flow
Sometimes the cap is just a fact of life. If your agency model relies on freelancers and you are loss-making, the cap will bite. The best you can do is calculate it early and factor it into your cash flow projections. Do not budget for the full payable credit if you know the cap will reduce it.
How to Check Your Position Before You Claim
Before you submit an R&D claim, run this simple test:
- Calculate your total qualifying R&D costs (staff, subcontractors at 65%, software, consumables)
- Calculate the enhanced expenditure (186% of qualifying costs)
- Calculate the payable credit (10% of the surrenderable loss)
- Calculate your total PAYE and Class 1 employer NI paid in the period
- Compare the two figures
If the payable credit is higher than the cap, you have a problem. The difference is the amount you will not receive. You need to decide whether the claim is still worthwhile, or whether to restructure your approach.
I have seen agencies abandon R&D claims entirely because the cap reduced the benefit to almost nothing. That is a shame if the underlying work genuinely qualifies. But it is better to know before you submit than to receive a letter from HMRC six months later telling you your credit has been reduced.
What HMRC Looks For
HMRC is increasingly scrutinising R&D claims from agencies. The PAYE-NI cap is one of the first things they check. If your claim shows high subcontractor costs and low PAYE-NI, expect questions.
They will also look at:
- Whether the subcontractor costs genuinely relate to R&D activities
- Whether the 65% restriction has been applied correctly
- Whether connected party rules have been followed
- Whether the R&D project meets the definition of "advancement in science or technology"
Agencies in particular get challenged on the last point. Building a website using existing frameworks is not R&D. Building a new content personalisation engine that solves a technical problem no one has solved before, that is R&D. The distinction matters.
If you are claiming R&D credits as a digital or creative agency, make sure your technical narrative is strong. HMRC has a dedicated R&D unit that reviews claims, and they know the agency sector well. A weak narrative combined with a cap issue is a recipe for a full enquiry.
Final Thoughts
The PAYE-NI cap on R&D claims is not going away. It is a permanent feature of the SME R&D scheme, and it directly affects agencies that rely on subcontractors. The best defence is awareness. Know your cap figure before you claim. Plan your R&D spend with the cap in mind. And if your agency model is heavily reliant on freelancers, accept that your R&D claim will be smaller than the qualifying costs suggest.
If your contractor mix has changed in the last 12 months or you are planning a significant R&D project, ask your accountant before you start spending. A quick calculation now can save you thousands in lost credit later.
At Agency Founder Finance, we are ICAEW qualified accountants who work exclusively with agency founders. We see the PAYE-NI cap catch people out every year. If you want to check whether your claim is at risk, get in touch. We will run the numbers and tell you where you stand.