There are two distinct questions buried inside “when do I pay tax on crypto?”. The first is when a taxable event occurs: the moment the tax clock starts. The second is when you must report and pay: the Self Assessment filing and payment deadlines. Conflating them is the most common source of late-filing penalties for crypto holders. This page separates both clearly.
The short answer: tax arises at disposal or at receipt, not at purchase or during holding
Under HMRC guidance, a Capital Gains Tax point arises when you dispose of a cryptoasset: selling for pounds, swapping for another token, spending on goods or services, or gifting to someone other than a spouse or civil partner. An Income Tax point arises when you receive tokens as a reward for mining, staking, or a qualifying airdrop, valued in sterling at the moment of receipt. Buying, holding, and moving tokens between your own wallets are not taxable events.
The deadlines are separate: register for Self Assessment by 5 October after the tax year ends, and file and pay by 31 January the following calendar year. Both are standard Self Assessment dates; crypto has no special calendar.
When a Capital Gains Tax point occurs
A CGT disposal occurs at the moment you sell, swap, spend, or gift crypto (except to a spouse or civil partner), valued in sterling at that instant. The gain or loss is calculated against your original acquisition cost using s104 pooling. Four types of event trigger a disposal:
- Selling for fiat. Converting tokens to pounds (or any fiat currency) is the most obvious disposal.
- Swapping one token for another. A crypto-to-crypto swap is a disposal of the token you gave up, at its sterling market value at the moment of the exchange. “I never cashed out to pounds” is not a defence under HMRC rules. For a worked breakdown of the swap mechanic, see our post on why crypto-to-crypto swaps are taxable disposals.
- Spending crypto on goods or services. Paying for something in crypto is a disposal of the tokens used, at their sterling value on the date of payment.
- Gifting to a non-spouse. Gifting to anyone other than a spouse or civil partner is a disposal at market value, even if no money changes hands. Transfers to a spouse or civil partner are no-gain/no-loss (see below).
The CGT estimator can help you model the gain on a straightforward disposal. It states its simplifications and is a scenario tool, not a filing-ready calculation; same-day and 30-day bed-and-breakfast override rules are out of scope of any stateless web tool.
When an Income Tax point occurs
An Income Tax point arises when you receive tokens as a reward for an activity. The taxable amount is the sterling value of the tokens at the moment of receipt. That same receipt value then becomes your base cost for CGT when you later dispose of those tokens.
- Mining rewards are taxable as miscellaneous income (or trading income if the mining amounts to a trade) at the point of receipt, per HMRC crypto21150. See our guide to mining rewards and the £1,000 allowance for further detail.
- Staking rewards follow the same receipt-then-disposal two-step as mining, per HMRC crypto21200. See our post on the staking tax two-step.
- Qualifying airdrops. An airdrop is taxable as income only if you received it in return for something, such as a service or an expectation of doing something. A genuinely unsolicited airdrop received for nothing is not income at receipt; it enters CGT at its acquisition value, per HMRC crypto21250.
- Salary paid in crypto. Employment income paid in tokens that are readily convertible assets is taxable as earnings through PAYE at the point of receipt, per HMRC crypto42000.
When you do NOT pay tax
Several common actions create no tax point at all under HMRC rules. Buying crypto, holding crypto, transferring tokens between your own wallets, and transferring to a spouse or civil partner are all outside the scope of an immediate tax charge.
- Buying crypto. Acquiring tokens for pounds creates no disposal. It sets your base cost in the s104 pool, which matters later.
- Holding crypto. Unrealised gains accrue silently. There is no mark-to-market or wealth tax on crypto holdings in the UK.
- Moving between your own wallets. A transfer between two addresses you control is not a disposal. You must be able to demonstrate that both wallets belong to you; if records are absent, HMRC may treat it as a disposal to an unknown third party.
- Transfers to a spouse or civil partner. These are no-gain/no-loss under HMRC CGT gift rules. The receiving spouse inherits the original base cost and the transfer is not a disposal. This is a legitimate planning lever: it allows a couple to use both annual exempt amounts (£3,000 each for 2026/27) and both basic-rate bands before a higher rate applies.
The deadlines that matter: the Self Assessment calendar
Crypto uses the standard Self Assessment calendar. There are no crypto-specific dates. The two deadlines that apply to every holder who has a reportable event are the 5 October registration deadline and the 31 January filing and payment deadline.
| Deadline | What it is | HMRC source |
|---|---|---|
| 5 October (after the tax year ends 5 April) | Register for Self Assessment if you have not filed before and have reportable crypto gains or income | gov.uk/register-for-self-assessment |
| 31 January (following calendar year) | File your Self Assessment return and pay any tax due, including CGT on crypto disposals and Income Tax on crypto receipts | gov.uk/self-assessment-tax-returns/deadlines |
| 31 January (same deadline) | Pay any balancing payment; also the second payment on account if one is due | gov.uk/self-assessment-tax-returns/deadlines |
The SA108 supplementary pages (capital gains summary) now include dedicated cryptoasset entries. Your Self Assessment return is where all crypto disposals and income receipts for the year are declared, per HMRC's SA guidance.
If you need help with filing, the crypto Self Assessment service page sets out how we handle the full return, from reconciling exchange data to completing the SA108.
When you must report even though no tax is due
Having no tax liability after the annual exempt amount is applied does not automatically mean you have nothing to report. Where your total disposal proceeds for the year exceed the HMRC reporting threshold, those disposals must be declared in Self Assessment regardless of whether any CGT is actually owed.
The threshold is set by HMRC and applies to total proceeds, not to gains. An investor with a high volume of swaps can easily breach it even in a year of net losses. Because each crypto-to-crypto swap counts as a separate disposal, the threshold is reached faster than most holders expect. HMRC's reporting and paying Capital Gains Tax page gives the current figure and explains when reporting is required.
Failing to report when proceeds exceed the threshold is a compliance failure even if no tax is owed. It is the same obligation as if you had sold a house: proceeds trigger reporting, not just net gains.
When to get help: CARF makes late-and-quiet the wrong strategy
From 1 January 2026 UK cryptoasset platforms are required to collect user and transaction data under the Cryptoasset Reporting Framework (CARF). The first report to HMRC is due between 1 January 2027 and 31 May 2027, covering all transactions in the 2026 calendar year. Annual reports follow by 31 May each year thereafter.
The era of “HMRC cannot see my exchange activity” is formally over. Platforms are now reporting the same data structure used internationally under OECD CARF. HMRC will be able to cross-reference exchange records against Self Assessment returns filed for 2025/26 and subsequent years.
For a full breakdown of what data is collected, which platforms are in scope, and what this means for past years, see our post on CARF and crypto reporting from 2026.
If you have years of unreported disposals or income, the window for an unprompted voluntary disclosure is shorter than it once was. An unprompted disclosure secures the lowest available penalty range. The HMRC disclosure service page explains the process; the disclosure estimator gives a rough indication of the years and amounts in scope before you commit to anything.
The investor hub maps out the full picture for holders building a position over time, including loss harvesting, annual exempt amount use, and spouse-transfer timing. If your situation involves multiple years, mixed events, or DeFi activity, getting the return filed correctly is usually faster and cheaper than fixing it after an HMRC enquiry.