Outsourced Corporation Tax Returns for UK Accounting Firms
Accurate CT600 preparation and HMRC filing support delivered in 5 working days, reviewer ready, senior CA reviewed, and packaged for clean sign off at a fraction of the cost.
Built for UK Tax Practices of Every Size.
Whether you face a growing CT backlog, need cover during filing peaks, or want to free up senior staff for advisory work, our corporation tax service slots directly into your workflow.
Solo and Small Practices
- Affordable per return pricing, no retainer
- No minimum volume commitment
- Same 5 day turnaround from day one
- Works inside your existing tax software
Growing Tax Practices
- Scale capacity instantly at filing peaks
- No permanent headcount required
- Dedicated account contact for your firm
- Senior CA reviewed output on every file
Mid Size and Multi Office Groups
- High volume CT capacity on demand
- Group relief and consolidation support
- Monthly volume reporting and SLA tracking
- R&D, RDEC, and marginal relief handled
Everything Covered,
Computation to Filing.
From raw accounts to iXBRL tagged CT600 return. We handle every stage of corporation tax preparation so your team focuses on client relationships and sign off.
CT600 Return Preparation
- CT600 corporation tax return preparation
- Tax computation schedules with full workings
- Capital allowances (AIA, FYA, WDA) schedules
- Deferred tax calculations and disclosures
Reliefs and Claims
- R&D tax credit computation and supporting notes
- Loss relief claims and surrender schedules
- Group relief allocations and surrenders
- Associated company rules and marginal relief
Compliance and Filing
- HMRC electronic filing support and iXBRL tagging
- Interest and penalties exposure summary
- Prior year adjustment and error correction notes
- Instalment payment computation for large companies
Reviewer Ready Delivery
- Open point query log with variance explanations
- Reviewer handover pack with sign off checklist
- Version controlled file delivery
- Revisions and amendments included at no extra cost
Your clients' software.
Our team knows it.
No onboarding friction. No tool switching. We step straight into the software your practice already runs on and get to work from day one.
Talk to our team
Outsource CT600: But Why?
Because your senior team's time is worth more than corporation tax preparation. Here's exactly what you gain.
Save Up to 60% in Costs
Replace expensive internal tax preparation time with expert offshore support. Pay per return, not per headcount.
Scale at Peak Season Instantly
Add CT preparation resource during your April to June and October to December filing peaks without any permanent commitment.
Senior CA Reviewed Every File
Every CT600 is quality checked by a qualified CA before delivery. You receive reviewer ready output, not a draft that needs fixing.
No Software Migration
We work directly inside TaxCalc, IRIS Tax, CCH, or Alphatax from day one. Your workflow and templates stay exactly as they are.
GDPR Secure from Day One
NDA and DPA signed before work begins. Encrypted file transfer, role based access, and full GDPR compliance throughout.
Six Reasons UK Firms Choose Us for Corporation Tax.
Expert reviewed CT600 returns, guaranteed turnaround, and seamless software compatibility, from the only outsourcing partner built specifically for UK accounting and tax practices.
Up to 60% cost saving
Reduce corporation tax preparation costs compared to internal staff time, without sacrificing review quality or accuracy.
5 day turnaround
Consistent delivery in 5 working days from receipt of signed accounts and trial balance, even at peak filing season.
HMRC compliant returns
All CT600 returns prepared in line with current HMRC requirements. R&D, marginal relief, and group relief scenarios handled correctly.
Senior CA reviewed output
Every CT file is quality checked by a qualified CA before delivery. No unreviewed work leaves our team.
Scalable peak capacity
Add tax preparation resource instantly during the spring and autumn filing peaks. Scale back when pressure eases.
GDPR secure delivery
NDA signed before work begins. Encrypted file transfer, role based access controls, and full GDPR compliance throughout.
How It Works
Share Signed Accounts
Secure upload of signed accounts and supporting schedules
CT600 Prepared
Computation and return prepared by CT specialists
Senior CA Review
Reviewed by an experienced senior CA
Quality Check
Multi level quality assurance before delivery
Reviewer Ready Delivery
Delivered in 5 working days, ready for client sign off
“Probal Global handles our entire CT600 preparation workload during the April and October filing peaks. The computations arrive reviewer ready with a clear open point log, our tax manager just signs off rather than preparing from scratch. We've saved over £30k annually and not once missed an HMRC deadline.”
£30k+
Annual saving on CT preparation
Probal Global vs Your Other Options.
See why UK practices choose dedicated outsourcing over internal preparation or freelancers for corporation tax work.
Real questions from UK accountancy practices answered honestly.
If you're considering bringing in external support for your construction clients, you probably have a few questions. Here are the ones we get asked most, with straight answers.
Still have questions? Get in touchYes. We work directly inside your existing tax software so there is no migration and no disruption to your internal review workflow. We adapt to your file structures and templates from day one.
Yes. We prepare R&D tax credit computations including the technical narrative template, qualifying expenditure schedule, and supporting documentation for both SME and RDEC schemes.
Capacity scales instantly. Most firms add dedicated CT resource from us during their spring and autumn peaks. Work is allocated the same day it arrives and turnaround is maintained at 5 working days.
Yes. We handle group relief surrenders, loss carry back and carry forward claims, and associated company rules including marginal relief calculations across the group.
We sign an NDA and DPA before any work begins. All files are transferred via encrypted channels. No client data is stored after delivery. We are GDPR registered and ISO 27001 aligned.
Revisions based on reviewer feedback are included at no extra charge. We aim to turn around revision files within 24 hours of receiving your comments.
Free Trial Available
Try Probal Corporation Tax Free.
10 Hours, No Cost, No Commitment.
Send us a real client file. We will prepare the CT600 and computation in your software, return a reviewer ready pack in 5 working days, and let the quality speak for itself.