Worldwide Disclosure Facility Calculator

What is the Worldwide Disclosure Facility?

The Worldwide Disclosure Facility (WDF) is the route HMRC set up for anyone who needs to correct a UK tax position that relates, wholly or partly, to an offshore matter – undeclared foreign rental income, overseas investment income or gains, unremitted income brought into the UK, or assets or accounts held abroad that were never properly reported. Disclosures are made through HMRC's Digital Disclosure Service (DDS), an online system built for this purpose. The WDF was introduced alongside the international Common Reporting Standard, under which most tax authorities now automatically exchange account and asset data with each other – so HMRC increasingly already knows, or will soon know, about offshore holdings before a taxpayer discloses them. This calculator estimates the tax, penalty range and assessable years you might be looking at, and explains the WDF process step by step.

How the calculator works

Enter the total unpaid tax you believe is owed across all the affected years, choose the behaviour that best describes why the tax went undeclared, say whether this is an unprompted disclosure (you are coming forward before HMRC contacts you) or a prompted one (HMRC has already been in touch), and select the territory category for where the money or asset is held. The calculator applies HMRC's published penalty percentage ranges for the behaviour and prompting you selected, then applies the offshore territory uplift, to give a total estimated liability range. It also flags the likely assessable years based on your behaviour and territory.

Assessable years: how far back can HMRC go?

The number of tax years HMRC can assess depends on why the tax was not declared. As a general rule: 4 years for an innocent mistake despite taking reasonable care, 6 years for careless behaviour, and up to 20 years for deliberate behaviour. For offshore income, gains and assets specifically, legislation introduced a minimum assessable period of 12 years that can apply even to non-deliberate errors, unless the territory involved has automatic exchange of information arrangements with HMRC (broadly, Category 1 territories) – in which case the standard 4/6/20-year limits apply instead. This extended offshore time limit is a major reason offshore cases often end up covering far more years, and far more tax, interest and penalty, than an equivalent onshore error.

Penalties: 0% to 200% of the tax owed

HMRC's penalty framework for inaccuracies and failures to notify starts from the behaviour involved: broadly 0–30% of the tax for careless errors, 20–70% for deliberate but not concealed behaviour, and 30–100% for deliberate and concealed behaviour, with the lower end of each range reserved for unprompted disclosures and the upper end more likely where HMRC prompted the disclosure. For offshore matters, these percentages are then increased depending on how cooperative the territory is: broadly unchanged for Category 1 territories (those with strong automatic information exchange with HMRC), up to 1.5× for Category 2, and up to 2× for Category 3 (the least cooperative territories) – which is how a deliberate and concealed offshore case can reach a penalty of up to 200% of the tax owed. Within any range, the exact penalty is reduced according to the quality of your disclosure: telling HMRC everything, helping HMRC understand it, and giving HMRC access to records all reduce the final figure.

Step by step: making a Worldwide Disclosure Facility disclosure

1. Register your intention to disclose through HMRC's Digital Disclosure Service, using a Government Gateway account. You do not need final figures at this stage.
2. Gather the facts for every affected tax year – income, gains, dates, exchange rates and the reason the tax was not declared, since this determines the behaviour category.
3. Calculate the tax, interest and your own estimate of the penalty for each year within the 90-day window HMRC gives you after registration.
4. Submit the disclosure and payment (or propose a time-to-pay arrangement if you cannot pay in full) through the DDS.
5. Respond to any HMRC review – HMRC can accept the disclosure, ask questions, or open a formal compliance check if it considers the disclosure incomplete or the penalty too low.

Worldwide Disclosure Facility vs other routes

The WDF is one of several HMRC disclosure routes and is not always the right one. The Let Property Campaign is specifically for undeclared UK residential rental income and generally offers a more standardised penalty structure for that narrower situation. The Contractual Disclosure Facility is used where HMRC suspects serious tax fraud and works very differently, offering immunity from criminal prosecution in exchange for full cooperation. If your situation is domestic only, or spans several types of error, our general HMRC Voluntary Disclosure Penalty Calculator compares prompted and unprompted penalties across facilities. Using the wrong facility, or missing offshore-specific rules, can result in a higher penalty than necessary, so get this right before you register.

Worked example

Aisha has £18,000 of undeclared tax relating to rental income from a property held in a Category 2 territory over several years, which she failed to declare because she wrongly assumed foreign rental income was not taxable in the UK – classed as careless, not deliberate. She comes forward unprompted. The base careless/unprompted penalty range is 0–30% of the tax; with the Category 2 uplift of ×1.5, her effective range becomes 0% to 45%, or £0 to £8,100. Because the disclosure is careless rather than deliberate, HMRC would normally look back 6 years, though the 12-year offshore minimum could extend this since her territory is not Category 1. Her total estimated liability, before interest, is therefore in the region of £18,000 to £26,100, with the final figure depending on how complete and cooperative her disclosure is.

Frequently asked questions

What is the Worldwide Disclosure Facility?

The Worldwide Disclosure Facility (WDF) is HMRC's route for telling HMRC about a UK tax liability that relates wholly or partly to an offshore matter, such as undeclared foreign income, gains or assets. Disclosures are made online through HMRC's Digital Disclosure Service.

How many years can HMRC go back under a Worldwide Disclosure Facility case?

It depends on behaviour and, for offshore matters, the source territory. Broadly: 4 years for an innocent error, 6 years for careless behaviour, and up to 20 years for deliberate behaviour. For most offshore income and gains, a minimum assessment period of 12 years can apply even for non-deliberate errors, unless the territory has automatic exchange of information with HMRC.

What penalty could I face under the Worldwide Disclosure Facility?

Penalties range from 0% (genuine reasonable excuse) up to 200% of the tax owed for deliberate and concealed behaviour involving the least cooperative offshore territories. The base penalty depends on behaviour and whether the disclosure is prompted or unprompted; offshore cases can then be increased by up to 100% extra depending on the territory involved.

How long do I have to complete a Worldwide Disclosure Facility disclosure?

Once you register your intention to disclose, HMRC gives you 90 days to gather the figures, complete the disclosure and pay what is owed (or agree time to pay). You do not need exact figures to register – the 90 days is for working them out.

Is the Worldwide Disclosure Facility the same as the Let Property Campaign?

No. The Let Property Campaign is specifically for undeclared UK residential rental income. The Worldwide Disclosure Facility is for offshore matters generally, including foreign rental income, foreign investment income, gains on overseas assets and unremitted income. Using the correct facility for your situation can affect the penalty applied.

Will using the Worldwide Disclosure Facility reduce my penalty?

Making an unprompted, full and complete voluntary disclosure normally attracts a lower penalty than if HMRC contacts you first (a prompted disclosure) or discovers the liability itself, so coming forward proactively through the WDF is usually the cheaper route even though it is not risk-free.

Do I need an accountant to use the Worldwide Disclosure Facility?

It is not a legal requirement, but offshore disclosures often involve several tax years, multiple currencies, complex behaviour classifications and penalty negotiation, so most people use a tax adviser experienced in disclosures, particularly where larger sums or several years are involved.

Sources: GOV.UK – Worldwide Disclosure Facility: make a disclosure; GOV.UK – Self Assessment penalties. Penalty percentages reflect HMRC's published behaviour-based penalty framework for inaccuracies and failures to notify, with the offshore territory uplift applied to the base range. Individual cases are assessed by HMRC and can differ from this estimate.