Why is my crypto tax number too high?

When a disposal cannot be matched to an acquisition, the cost basis defaults to zero and 100% of the proceeds are reported as profit. Nothing fails and no error is raised — the number is simply wrong, in the taxman's favour. On one reference dataset of 7 wallets and roughly 30,000 records, a leading incumbent reported a £336,248 gain where the reconciled position was a £176,494.84 loss.

Does Finality file my tax return?

No. Finality computes the figures and produces a box-mapped working paper for SA108 plus an evidence workbook. You own the return and file it yourself. Finality is software: it is not a firm of accountants, not a regulated tax adviser, and not affiliated with or endorsed by any tax authority.

Does Finality support tokenised equities and real-world assets (RWAs)?

Yes. A tokenised equity, tokenised stock, tokenised treasury bill or gold-backed token is an ERC-20 transfer on the same chains, so the same engine reads it, prices it by contract, pools it under Section 104 and matches its disposals to the acquisitions that paid for them. There is no separate RWA mode and no allowlist of supported tokens. What the engine does not do is decide what an asset is for tax — a token representing a share may be a security rather than a cryptoasset, and that is put to you as an open question.

How are NFTs treated differently from fungible tokens?

HMRC applies no pooling and no matching rules to non-fungibles (CRYPTO22200) — each is specifically identified. Running a non-fungible through the pooling engine would pool what must never be pooled and apply rules HMRC excludes, so they are handled by a separate engine.

What does Finality cost?

A tax year is bought once, not subscribed to: £20 up to 1,000 transactions in the filing year, £40 for 1,001–10,000, and £60 beyond that (a US filing year is $25, $50 or $75). Every prior year of history the computation needs is included at no extra charge, because cost basis is cumulative. Scanning is free and shows every finding and its value; the corrected figure, the working paper and the evidence workbook are what is paid for.

Does Finality need my exchange API keys?

No. Finality does not accept exchange API keys at all. You upload the CSV export from your exchange instead, so there is no credential to store. Sign-in does not use your wallet either — there is no message to sign and no transaction to approve.

Ask your AI assistant about your crypto tax

Connect Claude to your Finality account and ask about your position in plain words: your gains and losses for the year, what the figure does not yet cover, and which questions are still yours to answer. The answers come from your own scan, and every figure arrives with 2 downloadable documents - the working paper which you can copy and paste into your tax return and the evidence workbook.

Connecting is read only unless you choose otherwise, and you can disconnect at any time.

What an assistant can do

Your position, with its caveats

The figure, what it does not cover, and which way each gap moves it. An assistant gets the same caveats the working paper carries, on every answer that includes a figure.

What is still open

The questions only you can answer, with what each is worth, so you can work through them in conversation.

Your transactions and holdings

What you still held at the year end, and the transactions that need your review. Once the year is paid for, every transaction the scan read, with the figures that go on the return.

Links for the steps that stay yours

A link to upload an exchange export, to pay for a tax year, or to download your documents. You do each of those yourself, in your browser: the file goes to Finality from your own device, never retyped by an assistant, and nothing is bought until you complete the payment.

Full automation, if you choose it

Add and remove wallets and start scans. A removed wallet can be restored for 30 days, and everything an assistant changes is labelled with its name.

What it can never do

At any setting, a connected assistant cannot import or remove your transaction files, delete your account or change how you sign in, see your email address or card details, read the figures for a tax year you have not paid for. Text inside your transaction history that a stranger chose, such as a token’s name, reaches the assistant marked as data rather than as an instruction.

Connect Claude

On Claude’s website or desktop app, with a Free, Pro or Max plan:

Open Customize → Connectors and choose Add custom connector.
Name it Finality and paste this address: https://api.finalitycryptotax.com/mcp
Choose Add, then Connect.
Sign in to Finality when asked. You will see which assistant is asking and choose what it may do: Read only (selected for you) or Full automation. Choose Approve.
In a conversation, open the + menu, then Connectors, and turn Finality on.

On a Team or Enterprise plan, an organisation owner adds it once under Organization settings → Connectors, and each member then connects their own Finality account.

In Claude Code

claude mcp add --transport http finality https://api.finalitycryptotax.com/mcp

Then run /mcp in Claude Code and sign in to Finality.

Things to ask

“What is my 2025-26 position, and what is it not covering yet?”

“Which open questions are worth the most, and what does each one change?”

“Did any of my wallets return nothing in the last scan?”

“What did I still hold at the end of the tax year?”

Disconnecting

In Finality, open Account → Agent access. Every connected assistant is listed under Connected assistants, with what it may do and when it was last used. Disconnect ends its access on its next request.

Your data

When you ask your assistant a question, Finality sends it what it needs to answer, at your direction, and its provider then handles that under its own privacy policy, possibly outside the UK. What is sent, and what never is →