London accountants crypto tax support

Where cryptoasset tokens (also known as cryptocurrency) are held personally, this investment is usually undertaken in the hope of making a capital appreciation in its value or to make particular purchases. 

HMRC is clear that these holdings will usually be subject to Capital Gains Tax (CGT) if there is a gain when disposing of these assets by: 

If you have unpaid tax on cryptoasset gains, there is a specific voluntary disclosure service that can be used. This service can be used for exchange tokens (such as bitcoin), NFTs (non-fungible tokens) and utility tokens.

Before making a voluntary disclosure, you will need to: 

The number of years you must disclose unpaid tax depends on why it was not paid correctly. If you took reasonable care but still underpaid, you must disclose and pay for the last four years. If you did not take care, you must disclose for six years. However, if you deliberately failed to pay or knowingly gave incorrect information, you must disclose and pay for up to 20 years of unpaid tax.

Your disclosure must include all unpaid tax, interest and penalties. You can use HMRC’s calculators to work out the correct interest and penalty amounts. Once you submit your disclosure, HMRC will usually issue a payment reference number within 15 working days, and you must pay the full amount within 30 days of submitting a disclosure.

After reviewing your disclosure, HMRC will either send you a letter confirming acceptance of your offer or contact you if it cannot be accepted. If HMRC finds that you knowingly provided false or incorrect information, they may reopen your tax affairs and can impose higher penalties.

Source:HM Revenue & Customs | 03-11-2025
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Aitch
I'm Aitch, the Founder and CEO of CIGMA Accounting Ltd. As a Chartered Management Accountant and as a CIMA member, I've spent more than 16 years helping businesses, entrepreneurs, landlords, and individuals with tax planning, accounting, and HMRC compliance. As a chartered accountant in London, I'm passionate about making complex tax matters easier to understand and helping clients make confident financial decisions. Over the years, I've advised start-ups, SMEs, established companies, and high-net-worth individuals across a wide range of tax and accounting matters. My expertise includes Corporation Tax, Self-Assessment, Capital Gains Tax, Inheritance Tax planning, R&D tax relief, capital allowances, international tax, and resolving complex HMRC compliance issues. Whether clients need a business accountant, tax accountant, or strategic tax advisor, my focus is always on delivering practical advice that creates long-term value. One of my specialist areas is Making Tax Digital (MTD). I've worked extensively with businesses preparing HMRC's digital reporting requirements, helping them move to cloud accounting, improve financial processes, and adopt technology that makes compliance more efficient. I regularly speak at Making Tax Digital roadshows, industry events, and educational sessions in collaboration with Zoho Books, sharing practical insights into digital accounting, tax legislation, and the future of the profession. Many business owners looking for the best accounting firm in London are not simply searching for an accountant they're looking for trusted advice, responsive support, and long-term value. That's the approach I've taken in building CIGMA Accounting. My team and I work closely with businesses across London and the UK, providing accounting services, tax advisory, bookkeeping, payroll, VAT, company accounts, and strategic tax planning tailored to each client's goals. Through this website, I share practical guidance on UK taxation, Making Tax Digital, HMRC updates, Corporation Tax, Self-Assessment, and business finance. My aim is to provide reliable, straightforward information that helps business owners understand changing regulations, reduce compliance risks, and make informed financial decisions with confidence.
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