Corporation Tax · Wales
Corporation tax returns in Cilgwyn, Gwynedd
A company trading in Cilgwyn 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 Cilgwyn
Limited companies in Cilgwyn, Gwynedd 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 Cilgwyn, Gwynedd, 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
The IGI way of working, in Cilgwyn
No hourly rate and no surprise invoice. Cilgwyn 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 Cilgwyn client and chased before they arrive.
Online only, UK based. There is no office in Cilgwyn 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. Cilgwyn, Gwynedd 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 Cilgwyn, Gwynedd 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 Cilgwyn clients first, with the figures explained, and nothing leaves us until you say so.
Local facts
About Cilgwyn, Gwynedd
Cilgwyn, Gwynedd 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 |
|---|---|---|
| Talysarn | 0.7 mi | SW |
| Carmel, Gwynedd | 0.9 mi | N |
| Y Fron, Gwynedd | 1.0 mi | NE |
| Nantlle | 1 mi | E |
| Bwlch-y-llyn | 1 mi | NE |
| Ty'n-y-weirglodd | 1 mi | SW |
| Penygroes | 2 mi | W |
| Moel Tryfan | 2 mi | NE |
Worth knowing
Rules that come up in this work
CIS deductions
CIS turns construction subcontractors into advance taxpayers: a fifth of every labour payment goes to HMRC before they see it. Registering keeps the rate at 20% rather than 30%; gross payment status, for established businesses with a clean record, removes deductions altogether. The annual return is where the overpayment comes back, and filing it early brings the refund sooner.
Confirmation statements and identity verification
Every company must file a confirmation statement at least once a year, within fourteen days of its review date, with a £50 Companies House fee. Since November 2025 directors and people with significant control must also verify their identity with Companies House, and the confirmation statement is where existing officers confirm they have done so during the transition year.
Payments on account
If your Self Assessment bill exceeds £1,000 and less than 80% of your tax was collected at source, HMRC asks for two advance payments towards the following year, each half of the current bill, due 31 January and 31 July. The first year this happens the January payment is effectively one and a half times the bill. We model it in advance and show you how to reduce the payments if income is falling.
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.
Making Tax Digital for Income Tax
The biggest change to Self Assessment in a generation is Making Tax Digital for Income Tax, now live for higher-earning sole traders and landlords and arriving for the rest in stages. Quarterly updates are due by 7 August, 7 November, 7 February and 7 May, built from digital records. The practical consequence is that spreadsheet-and-shoebox bookkeeping is ending for anyone above the threshold.
Late filing penalties
HMRC's penalties for a late Self Assessment return are automatic: £100 the day after 31 January, £10 a day from three months late up to £900, then the greater of £300 or 5% of the tax at six and twelve months. Interest and separate late-payment penalties apply to the tax itself. Companies House charges £150 to £1,500 for late accounts, doubling for a second consecutive year.
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.
Questions
Corporation Tax questions from Cilgwyn
My CT600 is overdue. What now?
The £279 rescue fee gets it prepared and filed quickly from your accounts. The £100 late penalty is fixed, rising to £200 after three months and then to tax-geared penalties at six and twelve months, so speed matters. If there is a reasonable excuse we draft the appeal as part of the fee.
What is iXBRL and do I need to worry about it?
HMRC requires the accounts and computation attached to a CT600 to be tagged in iXBRL, a machine-readable format. We produce and validate the tagged files as part of the service. If another firm prepared your accounts we tag their figures; you never deal with it directly.
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.
How do I get started from Cilgwyn, Gwynedd?
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 Cilgwyn 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 Cilgwyn 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 Cilgwyn
Tell us what you need. You get one fixed fee in writing, and nothing is filed until you approve it.