Terms of Engagement

We will provide UK tax compliance services in relation to your crypto-asset transactions, which may include:

• Collecting and organising your transaction data from wallets, exchanges and other sources you specify;
• Calculating capital gains/losses and income amounts based on UK tax rules applicable at the time of preparation;
• Preparing supporting schedules and summaries for inclusion in your Self Assessment tax return or company tax return; and
• (If expressly agreed in writing) liaising with your tax return preparer or accountant and answering reasonable queries about our calculations.

We do not as part of this engagement:

• File tax returns on your behalf (unless separately agreed);
• Provide investment, financial, or legal advice;
• Provide regulated investment services or portfolio management;
• Perform an audit, assurance engagement or verification of records; or
• Represent you in any HMRC enquiry, dispute or investigation (unless agreed in a separate engagement).

Our work is based on UK law and HMRC practice in force at the time we complete the engagement. We are not responsible for changes in law or HMRC interpretation after that date.

You are responsible for:

• The completeness, accuracy and timeliness of all information, documents and explanations you provide;
• Ensuring you disclose all relevant wallets, exchanges, protocols and other sources of crypto-asset activity, including DeFi, NFTs, staking, airdrops and similar;
• Retaining your own records to meet HMRC requirements; and
• Reviewing any schedules or reports we provide, and notifying us promptly if you believe any information is incorrect or incomplete.

We will not verify the underlying accuracy or authenticity of data you provide (for example, CSV exports, API feeds or wallet exports). Our work is limited to organising and analysing that data on a reasonable-care basis.

You remain solely responsible for filing your tax returns and paying any tax due by HMRC deadlines unless we have separately agreed in writing to handle those tasks.

We are supervised for anti-money laundering purposes by the International Association of Bookkeepers (IAB). We must comply with the UK Money Laundering Regulations and related legislation.

Before we start work – and at any time during the relationship – we may:

• Request and verify proof of identity, address and other Know-Your-Customer information;
• Ask for information about the origin of funds and the economic purpose of your transactions; and
• Perform risk assessments and ongoing monitoring.

If you do not promptly provide information or documents we reasonably require to satisfy our AML obligations, we may:

• Delay or suspend work; and/or
• Terminate this engagement.

Where we know or suspect that money laundering or terrorist financing may be taking place, we are legally obliged to make a report to the appropriate authorities. In many cases we are not permitted to tell you that such a report has been made (“tipping-off” rules). Our legal duties override any contractual or confidentiality obligations to you.

We do not act for clients who use mixers, tumblers or other tools or structures designed primarily to conceal the provenance or trail of funds. If we identify such activity, we may terminate our engagement immediately and may be required to report our concerns.

Our fees are normally quoted as a fixed fee for the defined scope of work, based on:

• Volume and complexity of transactions;
• Number of wallets/exchanges/protocols; and
• Any additional advisory or support services agreed.

Where work required is materially greater than originally anticipated (for example, additional wallets, exchanges, or significant DeFi activity not previously disclosed), we may propose a revised fee. We will not proceed with chargeable additional work without your agreement.

Invoices are payable on presentation. We may withhold deliverables or suspend further work if invoices are unpaid.

We may accept payment by fiat currency and certain crypto-assets. Crypto payments will be converted into our base currency at the time of receipt using a reasonable market rate. Any exchange or network costs are payable by you.

We will keep your information confidential and use it only for:

• Performing this engagement;
• Complying with our legal and regulatory obligations, including AML; and
• Our legitimate business interests (for example, quality control, professional insurance, and internal analytics), in line with data protection law.

We may disclose information where required by law, regulation, court order, our professional body, insurers, or AML supervisors.

We may use anonymised and aggregated data for analytical and statistical purposes, provided you cannot reasonably be identified.

We act as a data controller in relation to personal data we process about you in connection with this engagement.

Our processing of personal data is described in more detail in our Privacy Policy, which we will provide separately and which is available at: /privacy. That policy forms part of these Terms of Engagement.

You confirm that you have authority to provide us with any third-party personal data (for example, information about beneficial owners or business partners) and to allow us to process it in accordance with our Privacy Policy.

Our work is limited to the services described in section 1. We will exercise reasonable skill and care in providing those services.

You acknowledge that:

• Crypto-asset records are often incomplete, inconsistent or generated from third-party systems outside our control;
• Market prices may differ between exchanges and over time; and
• Reasonable methodologies can produce slightly different tax outcomes.

We will apply reasonable and consistent methods, but we do not guarantee that HMRC or any other authority will agree with our calculations or interpretations.

To the fullest extent permitted by law:

• Our total aggregate liability to you, whether in contract, tort (including negligence) or otherwise, arising from or in connection with this engagement, is limited to the lower of £10,000 or three times the fees paid by you to us for the services to which the claim relates; and
• We are not liable for any indirect, consequential or special loss, loss of profits, loss of opportunity, or loss of data.

Nothing in these terms excludes or limits liability for fraud, fraudulent misrepresentation, or any other liability that cannot lawfully be excluded or limited.

Our work, reports and schedules are prepared solely for you for the purpose described in section 1.

No other person may rely on our work without our prior written consent. We accept no duty or liability to any third party who may receive a copy of our work.

You may provide our schedules to HMRC, your accountant or tax adviser as part of your tax affairs, but they must understand that our duty of care is owed only to you.

We commonly use email, client portals and other electronic tools to exchange information and documents. These methods carry inherent security and reliability risks that cannot be eliminated.

We will take reasonable steps to maintain security, but we cannot guarantee that communications will be free from interception, virus infection or other unauthorised access. You accept these risks when communicating with us electronically.

Where we use third-party software and services (for example, crypto data aggregation tools or secure file-sharing platforms), we will take reasonable care in their selection and use but are not responsible for failures outside our reasonable control.

We maintain continuity arrangements so that, in the event of death or incapacity of key personnel or other serious disruption, another suitably qualified professional can access your records to facilitate an orderly handover if needed. You consent to such limited access where reasonably necessary.

Either party may terminate this engagement by written notice at any time. We may terminate immediately if:

• You fail to pay our fees when due;
• You fail to provide information we reasonably require;
• You ask us to act in a way that is unlawful or inconsistent with professional or AML requirements; or
• Our risk assessment indicates that continuing the relationship is not appropriate.

On termination:

• Our fees for work performed up to the termination date will become payable;
• We may, subject to unpaid fees and legal duties, provide you or your new adviser with copies of data and schedules we hold; and
• We will retain or destroy records in line with our legal, regulatory and data-retention obligations.

We aim to provide a high-quality service. If you have any concerns or complaints, please contact us in the first instance at [email protected]. We will investigate and respond as promptly as we reasonably can.

If you are not satisfied with our response, you may have the right to escalate matters to our professional body or supervisory authority. Details are available on request.

These Terms of Engagement and any dispute or claim arising out of or in connection with them are governed by the laws of England and Wales.

The courts of England and Wales will have exclusive jurisdiction in relation to any such dispute or claim.

By proceeding with your quote, creating an account, uploading data, or otherwise using BlockBooks’ services, you confirm that you have read, understood and agree to be bound by these Terms of Engagement and our Privacy Policy. You acknowledge that these terms form a legally binding contract between you and BlockBooks Accounting Ltd (trading as BlockBooks) and that we will rely on them when commencing work. If you do not agree, you must not continue with the onboarding process or submit information to us. For corporate clients, you confirm that the individual completing this process is authorised to agree to these terms on the organisation’s behalf.