Trust Centre

OneSixth handles VAT-relevant accounting data on behalf of UK accountants and businesses. This page brings together how we keep that data safe, who we share it with, and the legal commitments we make.

Security

How we protect your data: encryption, isolation, access control, incident response.

Sub-processors

The third parties we use to deliver the service, with locations and purposes.

Data Processing Agreement

Our DPA, including UK GDPR Article 28 terms and international transfer safeguards.

Privacy Policy

What personal data we collect, why, how long we keep it, and your rights.

Cookie Policy

The cookies we set, their purposes and how to manage your preferences.

Status & changelog

Recent product updates and known incidents.

Contacts

Privacy / DPO: dpo@onesixth.app
Data subject requests: privacy@onesixth.app
Security / vulnerability disclosure: security@onesixth.app
General support: support@onesixth.app

Regulator

Option To VAT Limited is registered with the UK Information Commissioner's Office under registration number ZC197273 (download certificate). You may complain to the ICO at any time: ico.org.uk

UK VAT registration number: 523 3658 94 (effective 1 August 2026).

Independent security testing

Independent external vulnerability scan (Intruder, 24 July 2026): no issues detected across 45,936 checks (Critical / High / Medium / Low all zero) against www.onesixth.app (download report).