Terms of use

These Terms of Use ("Terms") govern your access to and use of DIY Accounting Submit™ ("the Service"), provided by DIY Accounting Limited (company number 06846849). By using the Service, you agree to these Terms and our Privacy Policy.

1. What the Service does

DIY Accounting Submit is a web application that helps UK businesses and their accountants send filings to HMRC and Companies House, and keep the books behind them. The Service offers:

• VAT (Making Tax Digital). View VAT obligations, liabilities, payments and penalties. Submit VAT returns to HMRC. View submitted returns and receipts.
• Income Tax Self Assessment (Making Tax Digital for Income Tax). Manage business details and obligations, send quarterly updates for self-employment and UK property, make annual submissions and adjustments, work with losses and claims, view tax calculations and make the final declaration. This is available in HMRC's sandbox (test) environment until HMRC approves the Service for production.
• Companies House. Search for a company. Change a registered office address or registered email address. File micro-entity accounts, small company accounts and confirmation statements. File a PSC verification statement. Changes of registered office and registered email address go to the live register. Accounts, confirmation statements and PSC verification statements are available in the Companies House sandbox (test) environment until Companies House approves the Service for live filing.
• Company Tax Return (CT600). Prepare a company tax return for HMRC. This is a preview.
• DIYA-GL books. Save and load DIYA-GL books in your account.
• MCP server. Read and edit a book, and file from it, through an AI assistant that supports the Model Context Protocol.
• Receipts and history. View receipts of earlier submissions.

Each feature shows its status (production, sandbox or preview) on its own page. A sandbox or preview feature sends nothing to the live service of HMRC or Companies House.

2. Eligibility and Account

• You must be a UK business, a sole trader or company, or an authorised agent or practice acting for one
• This Service is intended for business use only. If you are a sole trader, you are contracting in your business capacity, not as a consumer. Consumer protection laws (including the Consumer Rights Act 2015) may not apply to your use of this Service
• You must have valid HMRC Government Gateway credentials, or the Companies House sign-in that each Companies House filing needs
• You are responsible for maintaining the confidentiality of your login credentials
• You must not share your account with others or allow unauthorised access

3. HMRC Integration and OAuth

• The Service uses HMRC's OAuth 2.0 authorisation flow. When you authorise the Service, you grant us permission to access HMRC APIs on your behalf
• We will never request or store your HMRC Government Gateway password
• We store OAuth access tokens securely to enable API calls. You can revoke authorisation at any time through your HMRC authorised applications page
• You are responsible for the accuracy of data you submit to HMRC through the Service

For a Companies House filing, you authorise the Service to file for a company with the Companies House sign-in and the company authentication code that the filing needs.

If you file on behalf of a client as an agent, you must hold the client's authority before you file: the HMRC agent authorisation for an HMRC filing, and the client's company authentication code for a Companies House filing. You are responsible for holding that authority.

4. Acceptable Use

You agree not to:

• Use the Service for any unlawful purpose or in violation of any regulations
• Submit false, inaccurate, or misleading information to HMRC
• Attempt to gain unauthorised access to the Service, other users' accounts, or connected systems
• Interfere with or disrupt the Service or servers
• Use the Service to transmit malware, viruses, or harmful code
• Reverse engineer or decompile the Service beyond what the LICENSE file in our repository allows
• Use automated tools, bots, or scripts to access the Service without our written permission
• Attempt to circumvent rate limits or other technical restrictions
• Use the Service to build a competing product or resell API access to third parties without our express written consent
• Scrape, harvest, or collect data from the Service for commercial purposes

5. Data Processing and Privacy

• We process your personal data in accordance with UK GDPR and our Privacy Policy. Please review it carefully
• Data is encrypted at rest and in transit using industry-standard protocols (TLS 1.2+, AES-256)
• We use Amazon Web Services (AWS) as our infrastructure provider. Data is processed in the EU West (London) region. AWS is a GDPR-compliant data processor
• You have the right to access, export, and delete your data. Contact admin@diyaccounting.co.uk to exercise these rights. We will respond within 30 days

6. Data Retention

• User bundles: Retained while your account is active; deleted within 30 days of account closure
• HMRC submission receipts: Retained for 7 years in line with UK tax record-keeping requirements (HMRC requirement under VAT regulations)
• HMRC API audit logs: Retained for 30 days for compliance and troubleshooting; sensitive data is masked
• Authentication data: OAuth tokens expire per HMRC policy; refresh tokens deleted on logout or revocation
• Performance monitoring data: Raw events retained for 30 days; aggregated metrics (anonymized) longer
• Infrastructure logs: Retained for 30-90 days for security and operational purposes

7. Fraud Prevention Headers

In compliance with HMRC Making Tax Digital (MTD) regulations, the Service collects and transmits fraud prevention headers with each VAT return submission. This is a legal requirement for all MTD-compliant software.

Data collected includes:

• Public IP address
• Device identifier (generated fresh for each submission, not stored persistently)
• Browser user agent, timezone, screen resolution, and window size
• User identifier (Cognito user ID)
• Vendor information (application name and version)

This data helps HMRC identify and prevent fraudulent VAT submissions and supports criminal prosecutions for tax fraud. You consent to this collection when you authorise the Service through HMRC's OAuth flow. For full details, see the HMRC Fraud Prevention section of our Privacy Policy.

8. HMRC Software Vendor Status

DIY Accounting Submit is developed to comply with HMRC's Making Tax Digital requirements. The Service uses the official APIs of HMRC and Companies House and implements all required fraud prevention headers.

• VAT: production.
• Income Tax Self Assessment: sandbox, until HMRC approves the Service for production.
• Companies House accounts, confirmation statements and PSC verification statements: sandbox.
• Companies House registered office and registered email: production.
• Company Tax Return (CT600): preview.

The availability table shows the status of each filing and channel. We are committed to maintaining compliance with all HMRC requirements for MTD software vendors, including ongoing fraud prevention header compliance and security standards.

9. Service Availability

• We strive to maintain high availability but do not guarantee uninterrupted access
• The Service may be unavailable during maintenance windows (we will notify users where possible)
• HMRC API availability is outside our control. HMRC typically has planned maintenance periods
• We reserve the right to modify, suspend, or discontinue features with reasonable notice

10. Bundles, tokens, fees and subscriptions

Bundles

A bundle is the set of features your account can use. You can see the bundles open to you on the Bundles page. The Service has these bundles:

All prices are in pounds sterling.

Tokens

A token pays for one filing. A VAT return, a Self Assessment quarterly update, annual submission or final declaration, a Companies House filing and a company tax return each cost one token. Viewing obligations, returns, receipts and tax calculations costs no token. A bundle gives you its tokens when it starts and again each month if it refreshes monthly. Unused tokens do not carry over. Resident Pro has no token limit.

Creating a digital or physical pass to give to someone else costs 10 tokens.

Filing fee

Filing a confirmation statement with Companies House carries a charge of £61.35 for each filing, on top of the bundle and the token.

Subscriptions

• You buy Resident VAT, Resident and Resident Pro as a subscription through Stripe. Stripe takes your payment details; we do not store your card number
• A subscription starts when your payment succeeds and renews automatically at the end of each period (each month or each year) at the price shown when you subscribed, until you cancel
• You can cancel at any time. Cancellation stops the next renewal. You keep the bundle until the end of the period you have paid for
• We give at least 30 days' notice, by email, before a price rise. A price rise applies from your next renewal after the notice period ends. Paid bundles stay valid for the period you have paid for at the price you paid
• If a payment fails, we may suspend the bundle until the payment succeeds

Refunds

We do not refund a subscription or a filing fee, except where the law requires it or where the Service has been unavailable for more than 7 days in a row. A filing fee for a Companies House filing that Companies House rejects, because of a fault in the Service, is refunded or the filing is made again at no charge.

This Service is for business use. Consumer cancellation rights, including the 14-day cooling-off period, do not apply.

11. Intellectual Property

• The Service is free to use and its source is available. The source is licensed under the PolyForm Internal Use License 1.0.0, with an additional grant that lets an accountant or bookkeeper use the software to prepare accounts for their own clients. See the LICENSE file in the repository
• You may run your own copy of the Service on your own machine, for your own or your company's internal business. You may not host the Service for other people, under our name or any other, and you may not pass the source on
• DIY Accounting™, DIY Accounting Submit™ and DIYA-GL™ are trade marks of DIY Accounting Limited. The licence gives you no right to use them. See the TRADEMARKS.md file in the repository
• Third-party trademarks, including HMRC and AWS, are property of their respective owners

12. Limitation of Liability

To the fullest extent permitted by law:

• The Service is provided "as is" without warranties of any kind, express or implied
• We do not warrant that the Service will be error-free, secure, or uninterrupted
• We are not liable for any indirect, incidental, special, consequential, or punitive damages arising from your use of the Service
• Our total liability to you for any claims arising from the Service shall not exceed the greater of: (a) the amount you paid for the Service in the 12 months preceding the claim, or (b) fifty pounds (£50)
• You are responsible for ensuring the accuracy of data submitted to HMRC and compliance with all tax obligations. We are not tax advisors
• Nothing in these Terms excludes or limits our liability for death or personal injury caused by negligence, fraud, or any other liability that cannot be excluded by law

13. Indemnification

You agree to indemnify and hold harmless DIY Accounting Limited, its officers, employees, and agents from any claims, damages, or expenses arising from your use of the Service, your violation of these Terms, or your violation of any laws or regulations.

14. Force Majeure

Neither party shall be liable for delays or failures in performance resulting from circumstances beyond reasonable control, including but not limited to:

• HMRC system outages, maintenance, or API changes
• Changes to Making Tax Digital regulations or requirements
• Government or regulatory actions
• Natural disasters, pandemics, or other acts of God
• Cyber attacks, denial of service attacks, or security incidents affecting third-party infrastructure
• Failures of third-party infrastructure providers (including AWS)
• Internet or telecommunications failures

In the event of a force majeure event, the affected party shall notify the other party as soon as reasonably practicable and use reasonable efforts to mitigate the impact.

15. Security Incidents

• We implement industry-standard security measures to protect your data, including encryption, access controls, Web Application Firewall (WAF) protection, and regular security monitoring
• In the event of a data breach affecting your personal data, we will notify you and the ICO within 72 hours as required by UK GDPR
• We will also notify HMRC within 72 hours if the breach affects HMRC-related data or OAuth credentials

16. Termination

• You may terminate your account at any time by contacting admin@diyaccounting.co.uk
• We may suspend or terminate your access if you violate these Terms, for security reasons, or if required by law or by HMRC
• A cancelled subscription ends at the end of the period you have paid for
• Upon termination, your user data (bundles, saved DIYA-GL books and authentication tokens) will be deleted within 30 days. HMRC receipts will be retained for 7 years per legal requirements

17. Dispute Resolution

If a dispute arises between you and DIY Accounting Limited:

• Good faith negotiation: Both parties agree to attempt to resolve the dispute through good faith negotiation for a period of 30 days before initiating any formal proceedings
• Mediation: If negotiation fails, either party may propose mediation through an agreed mediator or a service such as the Centre for Effective Dispute Resolution (CEDR). Mediation costs shall be shared equally unless otherwise agreed
• Small claims: For disputes under £10,000, either party may bring a claim in the Small Claims Court of England and Wales
• Court proceedings: If mediation is unsuccessful or inappropriate, either party may commence court proceedings in accordance with Section 18 (Governing Law)

This clause does not prevent either party from seeking urgent injunctive relief where necessary.

18. Changes to Terms

• We may update these Terms from time to time. The "Last updated" date will reflect the most recent changes
• Material changes (including changes to fees, liability, or data processing) will be notified via email at least 30 days before they take effect
• Continued use of the Service after changes constitutes acceptance of the updated Terms
• If you do not agree to updated Terms, you may close your account before the changes take effect

19. Governing Law and Jurisdiction

• These Terms are governed by the laws of England and Wales
• Any disputes shall be subject to the exclusive jurisdiction of the courts of England and Wales, subject to the dispute resolution process in Section 17

20. Contact and Legal Entity

For questions about these Terms, data requests, or account issues:

As required by the Companies Act 2006, our company registration details are displayed above and on all official correspondence.

21. Source Code

The source code for this Service is available at github.com/diy-accounting-uk/submit.diyaccounting.co.uk under the PolyForm Internal Use License 1.0.0. Read it, run it on your own machine, and check what the Service does with your data.

The repository does not accept contributions, so please do not send a pull request. If you have found a security problem, tell us privately. The SECURITY.md file in the repository says how.

22. Affiliate and referral passes

These terms take effect when the first affiliate is approved.

A pass is a link that gives the person who follows it 7 days of free VAT submissions. The account that made the pass earns a commission when the person it brings in becomes a paying customer.

What you earn

• The commission is 33% of the net amount the referred customer pays us for their first 3 months. For an annual subscription, it is 33% of three twelfths of the annual payment.
• A customer who shares a pass earns credit on their own subscription. We release the credit 30 days after the payment it comes from. Credit is applied monthly. Credit is capped at 12 free months in total.
• An approved affiliate earns cash. We release cash 120 days after the payment it comes from. Cash is capped at £100 a month and £1,000 a tax year, and we pay it only when it reaches £5.
• We hold a commission for review when a cap is passed, when one pass brings in more than 5 conversions in a day, or when a signal of fraud appears.

Refunds and cancellations

If a referred customer is refunded, or disputes the payment, we reverse the matching commission. If we have not paid it, it is not paid. If we have paid it, we take it from your next commission. We take back unused credit.

Who can take part

• The scheme is for people who live in the United Kingdom and, for cash, hold a UK bank account.
• You must be 18 or over to be paid cash.
• You cannot refer yourself, and you cannot earn from an account you control.
• We approve each affiliate. We can decline an application, and we can end an affiliate at any time.

Disclosure

A post, message or page that carries your pass is an advert. Start it with #ad or a label that is just as clear, and follow our marketing guidance on how to describe the Service. We can end an affiliate who does not.

No employment

An affiliate is an independent person. You are not our employee or worker. You have no duty to promote the Service, no targets, and no set method or hours. You can stop at any time and so can we. We pay no expenses. You are responsible for any tax on what you earn.

Our discretion

We decide each payment. Our ledger of commission is final. We can change rates, caps and these terms on 30 days' notice, and we can end the scheme. No one has a right to a minimum or a future commission. Amounts we have not paid, and credit you have not used, lapse when you break these terms or when your affiliate status or account ends.