R&D Tax Credits · South West London
R&D tax credit claims in Castelnau
R&D tax credit claims for companies in Castelnau, starting with a free eligibility review that tells you honestly whether you have a claim. If you do, the full claim is £999 fixed: technical narrative, computation, the Additional Information Form and filing. The fee is published and the same in Castelnau as in every part of England.
from £999 · fixed, per claim
Next deadlines
- R&D claim deadline: 2 years after the end of the accounting period (and the pre-notification window of 6 months after the period for first-time claimants)
- Company tax return (CT600) due 12 months after your year end (a 31 December year end files by 31 December)
- Corporation Tax payment, 9 months and 1 day after your year end (a 31 December year end pays by 1 October)
- R&D claim deadline: 2 years after the end of the accounting period (and the pre-notification window of 6 months after the period for first-time claimants)
Who this is for
R&D Tax Credits for Castelnau
Limited companies in Castelnau that have tried to achieve an advance in science or technology and faced genuine uncertainty doing it: software firms building something that did not exist, manufacturers developing new processes or materials, engineering businesses solving problems off the standard path, and food, biotech and clean-tech companies with development spend to recover.
What is included
Everything inside the fixed fee
- Eligibility review against the statutory definition of R&D for tax purposes, with a written yes or no
- Advance notification to HMRC within six months of the period end for first-time and lapsed claimants
- Technical narrative for each project: the scientific or technological uncertainty, the advance sought and how it was resolved
- Qualifying expenditure computed: staff costs, subcontractors, externally provided workers, software, consumables and data
- The Additional Information Form completed and submitted before the CT600 is filed
- Claim entered on the CT600 and the relief or payable credit tracked through to HMRC's payment
How it works
R&D Tax Credits from Castelnau, step by step
Tell us your situation
A short message or call about what you do and what needs filing. We ask the questions that determine the right package and nothing more.
Fixed fee in writing
You receive one price for the work, confirmed by email before anything starts. It does not change if the job takes longer than we expected.
Send records, review the draft
Records come by WhatsApp or email. We prepare the draft, explain the figures in plain English and answer your questions.
We file, you get the receipts
Once you approve and the fee is settled, we submit electronically and forward the HMRC or Companies House acknowledgement the same day.
Why IGI
The IGI way of working, in Castelnau
The price for r&d tax credits is published on this page and is what a client in Castelnau pays. We confirm it in writing first, and the invoice matches the quote.
Deadline-first: the dates that matter for r&d tax credits are shown at the top of this page, diarised for every Castelnau client and chased before they arrive.
No appointments, no travel across South West London, no parking. Everything for r&d tax credits in Castelnau happens online, with a real person on the other end during UK working hours.
You get one contact for r&d tax credits, not a queue. Castelnau clients message the same person throughout and get an answer in working hours, usually within a few hours.
The output for Castelnau clients is never just a form. It is the form, a one-page summary of what it says, and a note of the decisions it points to for r&d tax credits.
Approval before filing is a rule, not a courtesy. For r&d tax credits in Castelnau, every submission to HMRC or Companies House follows your written go-ahead.
Local facts
About Castelnau
Castelnau is in South West London, within Richmond upon Thames, in the SW13 postcode district, England. Income tax in England follows the UK rates: 20% basic to £50,270, 40% higher to £125,140 and 45% additional, with the personal allowance of £12,570 tapered away above £100,000. National Insurance, VAT and Corporation Tax are UK-wide, and Stamp Duty Land Tax applies to property purchases.
| Place | Distance | Direction |
|---|---|---|
| Barnes | 0.6 mi | SW |
| Riverside, Hammersmith and Fulham | 0.7 mi | E |
| Mortlake and Barnes Common | 0.8 mi | SW |
| Chiswick Homefields | 0.8 mi | NW |
| Fulham Reach | 1.0 mi | NE |
| Ravenscourt Park | 1 mi | N |
| Palace Riverside | 1 mi | E |
| Munster | 1 mi | E |
Worth knowing
Rules that come up in this work
The VAT registration threshold
VAT registration is compulsory once taxable turnover in any rolling twelve-month period exceeds £90,000, or when you expect to exceed that in the next thirty days alone. The test is rolling, not by tax year, and includes zero-rated sales. Businesses regularly cross it without noticing, and late registration means accounting for VAT on sales where it was never charged to customers.
Corporation Tax rates and marginal relief
Companies pay Corporation Tax at 19% on profits up to £50,000 and 25% on profits over £250,000. Between those figures marginal relief applies, producing an effective rate that rises gradually and a marginal rate of 26.5% on each pound in the band. The thresholds are divided by the number of associated companies, so a director with two companies has thresholds of £25,000 and £125,000 for each.
Salary versus dividends
The salary-and-dividend split is the central planning decision for an owner-managed company. Salary costs employer National Insurance above £5,000 but is deductible; dividends are not deductible but attract lower personal rates and no National Insurance. The optimum changes each April with the thresholds and depends on the director's other income, so it should be set deliberately every year.
Director's loan accounts
Money taken from a company has to be something: salary, dividend, expense reimbursement or loan. If it is a loan and remains outstanding nine months after the year end, the company pays tax at the dividend higher rate on it until it is repaid. Clearing the balance with a properly declared dividend before the deadline, where reserves allow, is routine year-end work.
The Self Assessment calendar
Self Assessment runs on a fixed annual cycle. Registration by 5 October following the tax year, online filing and payment by 31 January, and a second instalment on 31 July for those making payments on account. The penalties for lateness are automatic and escalate monthly, which is why we file early and chase approvals well before the window closes.
Payments on account
A common surprise in Self Assessment is the January payment that is far larger than expected. That is the balancing payment for the year just ended plus the first payment on account for the year ahead, which HMRC sets at half of the bill just calculated. We put the figure in your hands months ahead and tell you how to adjust it legitimately when circumstances change.
Late filing penalties
Lateness is expensive in a way that compounds. For individuals, £100 immediately, then daily penalties, then percentage-based ones at six and twelve months, with interest running on unpaid tax throughout. For companies, Companies House penalties scale with delay and double on repeat, and HMRC adds its own for a late CT600. Filing on time is the cheapest tax planning there is.
Questions
R&D Tax Credits questions from Castelnau
What counts as R&D for tax purposes?
A project seeking an advance in overall knowledge or capability in a field of science or technology, through the resolution of scientific or technological uncertainty that a competent professional in the field could not readily resolve. Commercial novelty is not enough; routine development with known methods is not enough. The test is about the technology, not the product.
How much is the relief worth under the merged scheme?
For accounting periods starting on or after 1 April 2024 the merged scheme gives a 20% expenditure credit, taxable, so worth around 15% to 16.2% of qualifying spend net of tax. Loss-making companies spending at least 30% of total expenditure on R&D can claim the enhanced intensive rate, worth up to 27%.
What costs qualify?
Staff costs including employer NI and pension for time spent on R&D, externally provided workers at 65%, subcontracted R&D at 65% with new rules on who claims, software licences, cloud computing and data costs, consumables transformed or used up in the R&D, and some clinical trial payments. Capital spend, rent and marketing do not qualify.
What if HMRC opens an enquiry into an existing claim?
We review the claim, the narrative and the cost basis, tell you how robust it is, and quote a fixed fee for handling the enquiry before any work starts. Where a claim was overstated by a previous adviser, the best outcome is often an agreed reduction, and we say so rather than fight a losing position at your expense.
Can I claim for subcontracted work?
Under the merged scheme the company that decides to undertake the R&D and bears the risk generally claims, even if it subcontracts the work. Subcontractor costs are included at 65%. Overseas subcontractor and worker costs are largely excluded unless the conditions cannot be met in the UK. We apply the rules to your contracts.
Does claiming R&D relief increase my chance of an enquiry?
HMRC now checks a far higher proportion of claims than before 2023, so any claim carries some risk of questions. A claim with a clear technical narrative, costs that reconcile to the accounts and payroll, and a named competent professional behind it is answered quickly. We write claims to that standard.
Which deadlines matter most for r&d tax credits?
The next four dates that apply to r&d tax credits are shown at the top of this page, calculated from today. For Castelnau clients we diarise every one of them from the day you join and send reminders before each, so the work is done in good time rather than in the last week before a penalty.
How do I get started from Castelnau?
Message us on WhatsApp or email with a sentence about your business and what you need. We reply in working hours with any questions and a fixed fee for r&d tax credits. Once you confirm, we tell you exactly which records to send and the work begins. Most Castelnau clients are set up within a day.
Ready to fix your fee in Castelnau?
Tell us what you need. You get one fixed fee in writing, and nothing is filed until you approve it.