HMRC crypto records: what UK HNW clients and professionals should keep (and why it fails)

A practical record-keeping checklist for UK crypto holders and advisers: what to retain, how to structure it, and how to avoid 'reconstruction panic'.

Introduction

In the real world, HMRC risk usually appears later than clients expect. The problem is not that clients refuse to comply. It's that they cannot evidence what happened because the activity spans multiple exchanges, wallets, and years. Professional firms can add real value by preventing the most common failure: reconstruction panic. This is not tax advice. It is operational guidance on record keeping.

Why crypto record keeping breaks down

Clients often have: • multiple exchanges (opened over time, sometimes abandoned) • self-custody wallets and hardware devices • transfers between platforms for security, convenience, or fees • token swaps, staking, bridging, NFT activity • missing historic statements (especially on closed accounts) Add the fact that some clients trade frequently and others barely touch anything, and record standards become inconsistent.

What HMRC-style evidence looks like in practice

Your aim is to retain enough evidence to support: • acquisition price and date • disposal proceeds and date • fees and costs • the nature of non-trade events (gifts, forks, airdrops) • the identity of platforms involved • continuity of ownership (why funds moved between addresses)

The professional-grade 'records pack' checklist

1) Master platform register Create a list of every platform ever used: • exchange name and account email • approximate usage dates • KYC status (if known) • whether the account is still accessible • whether statements can be exported 2) Wallet register (no secrets) A register can exist without exposing private keys. Capture: • wallet type (hardware, mobile, desktop, multisig) • purpose (long-term hold, interaction wallet, business wallet) • device dependency (which phone/laptop matters) • where backups are held (location description, not the secret itself) 3) Transaction evidence baseline For each platform/wallet, retain: • CSV exports where available • monthly statements or annual summaries • screenshots of key confirmations only where necessary • fee reports • notes for large transfers ('moved from exchange to hardware wallet for security') 4) Cost basis support The biggest pain point for tax reporting is cost basis. Encourage clients to: • keep trade confirmations and conversions • keep funding history (bank deposits where relevant) • maintain a timeline of major buys/sells • keep records for wrapped assets or bridged tokens (where complexity increases) 5) Events that need extra notes These often cause confusion and should be explicitly recorded: • gifts to family members • receiving gifts • transfers into/out of entity structures • forks, airdrops, staking rewards • losses (including scams) and what evidence exists

How to structure it so it remains maintainable

HNW clients fail when record keeping becomes too heavy. The solution is to make it periodic: • quarterly check-in for active traders • every 4–6 months for typical holders • event-based updates after major changes (new exchange, new device, new wallet) A short review beats a once-a-year scramble.

Continuity links directly to compliance

If the client dies or becomes incapacitated, record keeping becomes exponentially harder. A continuity plan reduces compliance chaos because: • the inventory exists • access dependencies are known • authority is mapped • there is a process for executors Learn more about our approach to inheritance planning and security documentation.