Stress-free corporate tax outsourcing for accountants

From calculations to filing, we take the pressure off your team with expert precision and timely delivery.

Why you should outsource corporation tax services

Feeling buried under corporation tax work? You’re not alone. Between CT600 returns, R&D calculations, and deferred tax, the pressure on UK accountants is real. And it often leaves advisory tasks or business growth on the back burner.

Here’s what many accountants struggle with:

Constantly changing legislation

Tax laws, HMRC rules, and R&D relief guidelines evolve all the time, making it hard to stay fully compliant.

Complex returns

Handling multiple companies, inter-company transactions, or R&D claims can quickly overwhelm even experienced teams.

Time drain

Routine corporation tax work consumes valuable time that could be spent on advisory services or business growth.

Risk of errors and penalties

A small mistake can trigger HMRC fines, client dissatisfaction, or reputational risk for the firm.

Resource pressure during peak season

Short-staffed teams or sudden workload spikes can lead to burnout and backlogs.

Client expectations

Clients demand not just compliance but also accurate advice on minimising liabilities, claiming reliefs, and strategic planning.

How we help

Company tax returns, specifically the CT600 forms, require time to complete, must be accurate, and can prove costly for your clients if mistakes are made or if they are delayed. Letting us take on the heavy lifting means you have more time to assist your clients with your expertise. You can take the detailed reports and analysis we provide to guide your clients through future business decisions.

Heres how we make corporation tax easier for accountants

Here’s how we make corporation tax easier for accountants:

With Affinity Outsourcing managing your corporation tax, you get precision, compliance, and peace of mind—every return, every time.

Scope of our corporation tax outsourcing services

CT600 preparation and filing

Complete outsourced CT600 filing for UK accountants, ensuring compliance with HMRC guidelines and timely submissions.

Corporation tax calculations

Accurate calculation of taxable profits, capital allowances, and other adjustments tailored to client-specific accounting treatments and reliefs.

Deferred tax calculations

Specialist support in outsourced deferred tax calculations for accountants, ideal for firms handling complex client portfolios.

Loss relief and group relief claims

Expertise in identifying and applying relevant reliefs to optimise tax positions across client groups.

R&D tax credit support

Help with identifying eligible activities, calculating claims, and preparing supporting documentation.

Corporation tax compliance reviews

In-depth review of client records to identify errors, missed reliefs, or risk areas before filing.

HMRC correspondence handling

We manage client communication with HMRC (where authorised), ensuring clear, professional, and timely responses.

Accounting software used by us

Why choose us

Why choose us for Corporation tax outsourcing
Specialised UK tax expertise

Our team possesses deep, up-to-date knowledge of the complex and nuanced UK corporate tax landscape, ensuring robust compliance.

We ensure every CT600 return is prepared with precision and in full compliance with HMRC regulations—reducing the risk of penalties and ensuring peace of mind.

Our processes ensure timely, compliant, and accurate corporate tax returns, reducing the risk of HMRC penalties.

As your corporation tax filing outsourcing partner, we use your systems, checklists, and preferred formats — no disruption.

Whether you’re facing a sudden influx of work or consistent growth, we provide the flexible capacity to manage your fluctuating demands effortlessly.

Partnering with us allows your in-house tax professionals to concentrate on complex corporation tax cases and advisory work, enhancing your firm’s profitability and reputation.

What our clients say about us

Get inspired by the genuine stories of businesses we’ve helped and witness the remarkable difference our services can make.
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McKenzie Philips Tax Accountants
As a general practitioner for over 30 years I have experienced all the highs and lows of staff shortages, poor quality working papers, missed deadlines and the day-to-day pressure of work. Since being with Affinity I have not missed a single deadline, I have found the quality of their work to be excellent, and l can relax more, safe in the knowledge that they are there for me, taking care of both my clients and my Practice. I cannot recommend Affinity highly enough.
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Kevin Alderton & Team

The contrast with the previous outsourcing company could not have been clearer. Affinity provided us with a dedicated team in the UK and a team leader in India. We have an established system which allows us to prioritise our jobs making sure client satisfaction remains high. We like the ability to switch our usage on and off according to our work volumes and our capacity. Using Affinity Outsourcing has given us a significant competitive advantage and we continue to exploit this and increase our client numbers without compromising service levels.

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Artisan Accountants

Using Affinity Outsourcing has changed both my business and my lifestyle. I have an amazing work life balance and knowing that I have a back up plan if there is a reason why I can’t work has helped me enormously. The added value is that I have managed to increase my GRF and therefore the capital value of the business for my retirement without any stress. I cannot recommend this way of working highly enough.

Need help with CT600s, tax computations, or complex corporation tax cases?

Contact us today to discuss how we can become your trusted outsourcing partner.

Frequently Asked Questions

1. Can you work within tight deadlines for CT600 submissions?
Yes. We have dedicated workflows to meet submission deadlines even during peak periods, with urgent turnaround options.

Not at all. We work entirely behind the scenes as an extension of your team. You remain in full control of your client relationships while we provide the technical support.

Absolutely. We have experience handling complex structures, including group relief, capital allowances, and R&D claims.

You save on hiring senior tax professionals in-house. We provide the same high-quality output at a fraction of the cost, allowing you to serve more clients without increasing your overhead.