Calm, expert representation when HMRC opens an enquiry into your tax affairs.
Our UK tax investigation services give you an ACCA-qualified accountant to manage HMRC enquiries and compliance checks from the opening letter to final settlement. Whether HMRC has questioned a single figure on your Self Assessment, opened a full aspect enquiry into your company, or issued a COP8 or COP9 notice, we handle the correspondence, challenge unreasonable demands and work to minimise the tax, interest and penalties. You get fixed pricing, a named contact and replies within 72 hours, so you are never left guessing while the clock runs.
Most HMRC contact begins as a compliance check letter querying one or more specific entries, such as expenses, a property disposal or undeclared income. We review what HMRC is actually entitled to ask for, gather only the documents required, and reply within HMRC's deadlines (typically 30 days, with extensions negotiated where reasonable). Handling an aspect enquiry properly early often stops it escalating into a full enquiry.
For a full enquiry, HMRC examines the whole return. We act as your agent throughout, attend or decline meetings on your behalf, prepare the business economics and means analysis HMRC relies on, and keep the investigation focused on the figures in dispute rather than a wider fishing exercise. We also check HMRC has opened the enquiry within the statutory window, normally 12 months from the date the return was filed.
If HMRC raises a discovery assessment outside the normal enquiry window, the time limit depends on behaviour: 4 years for an innocent error, 6 years for careless behaviour and up to 20 years where the loss of tax is deliberate. We challenge invalid discoveries, test whether HMRC genuinely made a new discovery, and where appropriate argue that the assessment is out of time so it cannot stand.
Penalties hinge on behaviour. For inaccuracies, a careless error carries 0% to 30% of the extra tax, deliberate 20% to 70%, and deliberate and concealed 30% to 100%, with the lower end of each band reached through unprompted disclosure and full cooperation. We negotiate the behaviour category, maximise the reduction for telling, helping and giving access, and seek to have careless penalties suspended against future conditions so nothing is actually paid.
Where HMRC suspects a significant tax loss it uses Code of Practice 8, and where it suspects deliberate fraud it issues Code of Practice 9 with the Contractual Disclosure Facility (CDF). These are high-stakes investigations carrying up to 100% penalties and, in COP9, the alternative of criminal prosecution. We work alongside specialist tax counsel where needed, prepare the outline disclosure within the 60-day CDF window and the full disclosure report, and protect you from inadvertently widening the scope.
If you know something is wrong before HMRC asks, coming forward first secures the largest penalty reductions and removes the risk of a deliberate-behaviour finding. We prepare disclosures through the Digital Disclosure Service, the Let Property Campaign and the Worldwide Disclosure Facility, calculate the tax, interest and any penalty, and agree a settlement or time-to-pay arrangement. We also handle reviews and First-tier Tribunal appeals if HMRC will not settle reasonably.
You deal with one qualified person who knows your file, not a call centre. They speak to HMRC so you do not have to, and every letter and figure goes through someone who has handled enquiries before.
Our plans are priced at a clear £99, £199 or £499, agreed up front. You will not get a frightening hourly invoice on top of an already stressful investigation, and a 30-day money-back guarantee backs the work.
HMRC enquiries run on deadlines, and silence costs money. We commit to responding within 72 hours so documents go back on time, extension requests are made early and penalties for delay are avoided.
Many taxpayers accept HMRC's first penalty position. We challenge the behaviour category, push for the maximum reduction for disclosure and cooperation, and seek suspension of careless penalties, which can mean paying far less or nothing in penalties.
We pull the records HMRC needs straight from Xero, QuickBooks, FreeAgent or Sage, so reconstructing the position is quick and accurate. On a rolling monthly arrangement you can stay supported after the enquiry closes.
Understanding your business needs.
Crafting your custom accounting strategy.
Quick and easy integration.
Consistent monitoring and reporting.
CT600 returns, computations, and strategic planning to legitimately reduce your liability.
Read morePersonal tax returns prepared, optimised, and filed for directors, sole traders, and high earners.
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Read moreDisposal planning, reliefs, and computations for property, shares, and crypto sales.
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Enquiries are triggered by data mismatches (third-party reports from banks, platforms, Companies House), industry risk profiling, random selection, tip-offs, or unusual swings in your figures year-on-year. HMRC doesn't have to give a reason. The first letter looks intimidating but is usually a standard Section 9A or 12AC notice, the response in the first 30 days sets the tone for the whole enquiry.
COP8 covers cases where HMRC suspects significant tax loss but not deliberate fraud. COP9 is the Contractual Disclosure Facility, HMRC suspects deliberate fraud and is offering you immunity from criminal prosecution in exchange for a full, accurate disclosure within 60 days. COP9 is far more serious and you must never respond to one without specialist representation. We've handled both end-to-end.
We build the defence around the three irreducible tests, mutuality of obligation, personal service, and control, supported by your actual working practices, contracts, and the end client's evidence. CEST output, if any, is reviewed but rarely decisive on its own. The earlier we get involved (ideally before HMRC issues a determination), the stronger the position and the lower the penalty exposure.
Yes. Penalties scale by behaviour: 0-30% for careless errors, 20-70% for deliberate, and 30-100% for deliberate and concealed. Within each band, full unprompted disclosure and cooperation can cut the penalty to the minimum. Reasonable excuse arguments can remove penalties entirely in some cases. Our job is to position your facts in the band and percentage that costs you least.
For around £15-£30 a month, fee protection covers our professional fees if HMRC opens an enquiry, typically up to £100,000 of representation. Without it, defending even a basic aspect enquiry can cost £2,000-£5,000 in fees on top of any tax. Given HMRC opens enquiries on roughly 7% of small businesses each year, most clients add it once they see the maths.
Thirty minutes with an ACCA-qualified accountant. Most owners uncover £1,000-£3,000 in annual savings on the first call. If we are not the right fit, you walk away with a free tax review on the house.
