Accounting

Corporation Tax · Wales

Corporation tax returns in Dyffryn-mawr

Corporation Tax for Dyffryn-mawr companies whose accounts are prepared elsewhere, or who want a second pair of eyes on the computation before HMRC sees it. We reconcile the accounting profit to the taxable figure, apply the correct rate, and file the CT600 with iXBRL accounts attached. One fixed fee per return, no hourly billing, nothing filed until you approve.

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 Dyffryn-mawr

Limited companies in Dyffryn-mawr 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 Dyffryn-mawr, step by step

  1. 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.

  2. Agree the price

    The fee is confirmed in writing. There is no hourly billing and nothing added for questions during the work.

  3. 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.

  4. 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 Dyffryn-mawr

One fixed fee for corporation tax in Dyffryn-mawr, agreed in writing before any work starts and never changed part-way through the job, however long it takes us.

We work to the HMRC and Companies House calendar, not an appointment diary. Clients in Dyffryn-mawr get reminders at 60, 30 and 7 days before each date that applies to corporation tax.

No appointments, no travel across Wales, no parking. Everything for corporation tax in Dyffryn-mawr happens online, with a real person on the other end during UK working hours.

A named person handles your corporation tax from Dyffryn-mawr and knows the file, so you are not re-explaining your business to a different helpdesk each time.

We explain corporation tax in the words Dyffryn-mawr 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 Dyffryn-mawr clients first, with the figures explained, and nothing leaves us until you say so.

Local facts

About Dyffryn-mawr

Dyffryn-mawr 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.

Nearby places we also serve for corporation tax
PlaceDistanceDirection
Lower Common, Monmouthshire0.2 miSW
Glangrwyney0.7 miNW
Llangrwyney0.7 miNW
Aberbaiden Farm0.8 miSE
Gilwern0.8 miS
Pen-y-bont, Monmouthshire0.8 miSW
Llanwenarth1 miE
Maesygwartha1 miSW

Worth knowing

Rules that come up in this work

Making Tax Digital for Income Tax

Making Tax Digital for Income Tax began in April 2026 for sole traders and landlords with qualifying income over £50,000, extends to those over £30,000 in April 2027 and is planned for £20,000 in April 2028. It requires digital records in compatible software and four quarterly updates to HMRC each year, with a final declaration replacing the traditional return. Payment dates are unchanged.

Late filing penalties

Penalties are the clearest reason to work to deadlines. A Self Assessment return one day late costs £100 regardless of whether any tax is due; three months late adds £10 a day. Late company accounts start at £150 and reach £1,500, and double if the previous year was also late. None of this is negotiable afterwards except through a narrow reasonable-excuse appeal.

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.

The Self Assessment calendar

Four dates govern Self Assessment: 5 October to register, 31 October for paper returns, 31 January to file online and pay, and 31 July for the second payment on account. Missing the January date triggers an automatic £100 penalty before any tax is even considered, so we treat it as the fixed point around which the rest of the year is planned.

Director's loan accounts

The most common tax problem in owner-managed companies is an overdrawn director's loan account: drawings taken during the year that were never declared as dividends or salary. The company faces a 35.75% charge on the balance outstanding nine months after the year end, and the director may have a benefit in kind. We review the account before every year end to clear it properly.

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.

Corporation Tax rates and marginal relief

Corporation Tax is not a flat rate. Profits to £50,000 pay 19%, profits above £250,000 pay 25%, and the band between is taxed at an effective marginal rate of 26.5% through the marginal relief mechanism. Associated companies share the thresholds, which catches directors who own more than one company and is the most common cause of underpaid tax in owner-managed groups.

Questions

Corporation Tax questions from Dyffryn-mawr

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 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 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.

Is corporation tax in Dyffryn-mawr really the same price as elsewhere?

Yes. The fee published on this page is what a client in Dyffryn-mawr pays and what a client in any other part of Wales pays. It is confirmed in writing before work starts and the invoice matches the quote. Where a higher package applies because your situation is more complex, we say so at the quote stage, never afterwards.

Do you have an office in Dyffryn-mawr?

No. IGI Accounting is an online-only firm. We serve Dyffryn-mawr and every other UK postcode remotely, with records sent by WhatsApp or email and everything filed electronically. The absence of local premises is why the fee for corporation tax is the same in Dyffryn-mawr as anywhere else in the country, and why there is nothing to visit and nothing to print.

Start the conversation from Dyffryn-mawr

Tell us what you need. You get one fixed fee in writing, and nothing is filed until you approve it.

WhatsApp for a fixed quote