Corporation Tax · Wales
Corporation tax returns in Trefflemin
A company trading in Trefflemin pays Corporation Tax nine months and one day after its year end and files the CT600 three months after that. We handle both from your accounts, whether we prepared them or another firm did: standalone CT600 at £199, with a capital allowances review at £299, overdue rescue at £279. Fixed, agreed in writing.
from £199 · fixed, per return
Next deadlines
- Company tax return (CT600) due 12 months after your year end (a 31 December year end files by 31 December)
- 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)
- Companies House accounts due 9 months after your year end (a 31 December year end files by 30 September)
- Corporation Tax payment, 9 months and 1 day after your year end (a 31 December year end pays by 1 October)
Who this is for
Corporation Tax for Trefflemin
Limited companies in Trefflemin of every size below the large-company regime: companies whose accounts are prepared by another firm or in-house and need the tax return filed, companies with capital expenditure to claim, companies that have made a loss and want it used well, groups of associated companies, and companies whose CT600 is already overdue.
What is included
Everything inside the fixed fee
- Corporation Tax computation reconciling accounting profit to taxable profit, with every adjustment explained
- Capital allowances claimed in full: annual investment allowance, full expensing, writing-down allowances and the special rate pool
- Loss relief planned and claimed: carry back, carry forward and group relief where it applies
- Marginal relief and associated-company rules applied correctly between the 19% and 25% rates
- CT600 with supplementary pages, iXBRL-tagged accounts and computation, filed electronically with HMRC
- Payment note with amount, due date and HMRC reference, and reminders before the payment and filing dates
How it works
Corporation Tax from Trefflemin, step by step
Scope the job
We find out what you need filed, when it is due and what state the records are in, and tell you which fixed-fee package applies.
Agree the price
The fee is confirmed in writing. There is no hourly billing and nothing added for questions during the work.
Hand over the records
Photographs, PDFs, software access or a spreadsheet, sent however suits you. We confirm what we have and what is missing within two working days.
Approve, then we submit
You review the draft with our explanation, sign off, and we file. Receipts, copies and the next deadlines come back to you immediately.
Why IGI
What you get in Trefflemin
No hourly rate and no surprise invoice. Trefflemin clients know the fee for corporation tax before they send a single document, and it stays fixed.
Deadline-first: the dates that matter for corporation tax are shown at the top of this page, diarised for every Trefflemin client and chased before they arrive.
Online only, UK based. There is no office in Trefflemin to pay for, which is why the fee is the same here as anywhere in Wales; the work is done by people in the UK who answer the same day.
You get one contact for corporation tax, not a queue. Trefflemin clients message the same person throughout and get an answer in working hours, usually within a few hours.
We explain corporation tax in the words Trefflemin business owners use, not in accountant's shorthand, and we show our working so you can check it.
You stay in control of corporation tax: drafts go to Trefflemin clients first, with the figures explained, and nothing leaves us until you say so.
Local facts
About Trefflemin
Trefflemin is in Wales, Wales. Businesses in Wales file with the same HMRC and Companies House as England, and for now the Welsh rates of income tax equal the English ones, though the Senedd can vary them. The practical differences are Land Transaction Tax on property and Welsh-specific business support schemes, and company names and documents may be in Welsh.
| Place | Distance | Direction |
|---|---|---|
| Flemingston | 0.0 mi | N |
| Beggars Pound | 0.6 mi | S |
| Pound, Beggars | 0.6 mi | S |
| Brewis | 0.6 mi | W |
| Eglwys-Brewis | 0.6 mi | W |
| Castleton Park | 0.7 mi | SE |
| Sain Tathan | 0.8 mi | S |
| St Athan | 0.8 mi | S |
Worth knowing
Rules that come up in this work
The VAT registration threshold
The £90,000 VAT threshold is measured over any twelve consecutive months, which is why a strong quarter can tip a business over unexpectedly. Registration must follow within thirty days of the end of the month the threshold was crossed. Below the threshold, voluntary registration is worth considering when customers are VAT-registered businesses and costs carry VAT.
Director's loan accounts
A director's loan account records money moving between a director and the company that is not salary or dividend. If the director owes the company money nine months and one day after the year end, the company pays section 455 tax at 35.75% of the balance, refundable only when the loan is repaid. Loans over £10,000 are also a benefit in kind unless interest is charged at HMRC's official rate.
Salary versus dividends
Paying yourself from a company involves two routes with different tax treatment. Salary through payroll is a company expense and builds a National Insurance record; dividends come from post-tax profit at lower personal rates. Undocumented drawings that are neither become director's loans, with a 35.75% section 455 charge if not repaid within nine months of the year end.
CIS deductions
The Construction Industry Scheme affects both sides of a construction payment. Contractors must verify subcontractors, deduct the right amount, issue statements and file monthly, with penalties from £100 for each late return. Subcontractors suffer deductions on turnover and recover the excess at the year end. Limited company subcontractors offset deductions against PAYE monthly instead.
Confirmation statements and identity verification
The confirmation statement is the annual check that the public register is right: officers, registered office, SIC codes, shareholders and the PSC register. It carries a £50 fee and no financial penalty for lateness, but failure to file leads to compulsory strike-off. The identity verification regime introduced in November 2025 has added a further check to every statement.
The 60-day property CGT return
Selling UK residential property that was not your main home for the whole period of ownership triggers a separate Capital Gains Tax return, due within 60 days of completion along with payment of the tax. This is in addition to the annual Self Assessment. The gain is taxed at 18% or 24% depending on your income band, after the £3,000 annual exempt amount.
Crypto records and reporting
Crypto tax splits into capital gains on disposals and income on rewards, with different rates and different reporting. The £3,000 annual exempt amount and the 18% and 24% rates apply to gains; staking, mining and airdrop income is taxed at marginal income tax rates. HMRC's nudge letters to holders have increased sharply, and a voluntary disclosure before one arrives is treated far more leniently.
Questions
Corporation Tax questions from Trefflemin
What expenses are not allowed for Corporation Tax?
Business entertainment of customers, most fines and penalties, depreciation (replaced by capital allowances), general provisions, and the private element of mixed-use costs. Legal fees on capital items are also disallowed. The computation adds these back to accounting profit and we list every adjustment so you can see the effect.
Are dividends and salary treated differently for Corporation Tax?
Yes. Salary, employer National Insurance and employer pension contributions are deductible expenses that reduce taxable profit. Dividends are paid from profit after tax and are not deductible. This asymmetry is central to the salary-versus-dividend planning we do for directors.
What are associated companies and why do they matter?
Companies under common control count as associated, and the £50,000 and £250,000 thresholds are divided between them. A director who owns two companies has thresholds of £25,000 and £125,000 for each. Missing this is a common error that produces an underpayment and interest.
My company made a loss. What can be done with it?
A trading loss can be set against the company's other profits of the same year, carried back one year for a repayment of tax already paid, or carried forward against future profits. The right choice depends on cash flow and expected profits. We model the options and make the claim on the return.
What are capital allowances and what can I claim?
Capital allowances are the tax equivalent of depreciation. The annual investment allowance gives 100% relief on up to £1 million of qualifying plant and machinery a year; full expensing gives 100% on new main-rate assets without limit; cars and integral features go into pools at 18% or 6%. The £299 package reviews every asset purchase in the year.
When is Corporation Tax paid and the return filed?
Tax is due nine months and one day after the end of the accounting period; the CT600 is due twelve months after it. Companies with profits over £1.5 million pay by instalments instead. Interest runs on late payment from the due date, and a late return attracts a £100 penalty rising to 10% of the tax at twelve months.
How do I get started from Trefflemin?
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 corporation tax. Once you confirm, we tell you exactly which records to send and the work begins. Most Trefflemin clients are set up within a day.
Which deadlines matter most for corporation tax?
The next four dates that apply to corporation tax are shown at the top of this page, calculated from today. For Trefflemin 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.
Fixed fees, filed on time, for Trefflemin
Tell us what you need. You get one fixed fee in writing, and nothing is filed until you approve it.