AI Guides › Workbench
By Nigel Guy · 7 min read
If you earn from more than one place, your income probably lives in a payslip folder, a PayPal history, three invoices in your email, a marketplace dashboard and a bank app. You know roughly what comes in, and "roughly" feels fine until someone asks what you earned from side work last quarter, or the tax return arrives. The usual fix is a fresh spreadsheet that you abandon by March.
The rule: give every pound one category, one date and one source before you try to analyse anything. A consistent ledger is what makes the one-page summary possible. The prompt below builds the ledger, the summary and the list of things it cannot tell you.
| Option | What it does | Cost at time of writing | Best for | Catch |
|---|---|---|---|---|
| Claude, free plan, with a Project | Reads files you upload, builds a ledger and summary, keeps your instructions in a Project | Free; the Free plan allows up to 5 Projects | Trying the method once | Free-plan usage limits vary, so a long statement may stall |
| Claude Pro | Same, with unlimited Projects and more usage | $20 a month, or $17 a month billed annually ($200 upfront); about £16 and £13 at time of writing, so check the £ price at checkout | Monthly use across several streams | You are paying for a method a spreadsheet can also run |
| A spreadsheet you already own | Holds the ledger and does the sums with formulas | Whatever you already pay, often nothing | Keeping the master copy | You do the data entry yourself |
| GOV.UK allowance and Self Assessment pages | Authoritative rules on what must be reported | Free | Checking the tax side | They state rules, not your personal liability |
Code execution and file creation, which lets Claude analyse CSVs and produce .xlsx files, is available on all Claude plans and is switched on under Settings > Capabilities. The file limit is 30MB per file. Menus move, so check the current help page if yours looks different.
Before any prompt, decide what a row looks like. Every income event becomes one row:
| Date | Stream | Gross amount (£) | Source document | Status |
|---|---|---|---|---|
| 2026-09-28 | Client work | 850.00 | Invoice 0042 | Received |
Write four to eight streams, no more. A typical set: Salary, Client work, Brand deals, Digital product sales, Other sales, Interest and dividends, Refunds and one-offs. Anything that is not income, such as a loan, a transfer between your own accounts or a reimbursement, goes in a seventh bucket called "Not income", so it is visible and excluded rather than silently dropped.
Export a CSV or PDF from each place money lands: bank statements, payment processor reports, marketplace payout reports, plus invoices you have issued. Remove account numbers you do not need before uploading. Check your Claude privacy and data settings before you upload financial documents; I have not verified the current defaults here, so read them rather than assume.
Create a Claude Project called "Income ledger 2026-27", paste the prompt into the project instructions or the first chat, and upload your files.
You are a careful bookkeeping assistant for a UK individual with several income streams. You are not an accountant and you do not give tax advice.
Goal: turn my uploaded documents into (1) a clean income ledger and (2) a one-page summary I can read in two minutes.
My inputs:
- Streams, in this order: [YOUR_STREAM_LIST]
- Period: [START_DATE] to [END_DATE]
- Documents uploaded: [LIST_OF_FILES_AND_WHAT_EACH_IS]
- Known items that are NOT income: [TRANSFERS_LOANS_REFUNDS]
- Currency: GBP. Convert other currencies only if I give you the rate: [RATE_OR_NONE]
Steps:
1. List every file you can read and flag any you cannot. Stop and ask if something is unreadable.
2. Extract each money-in line. Assign it to exactly one stream from my list, or to "Not income" or "Unclear".
3. Never invent a stream. If a line does not clearly fit, mark it "Unclear" and give your best guess in a separate column.
4. Record each row as: Date | Stream | Gross amount (£) | Source document | Status (Invoiced, Received or Expected).
5. If a document shows only a net amount, record it as net and say so in a Notes column. Do not estimate gross.
6. Produce the one-page summary: total per stream, share of the total, the month with the highest and lowest total, and anything Expected but not yet received.
7. Add a section titled "What this cannot tell you", listing gaps such as missing months, net-versus-gross mismatches and streams with no documents.
Output: the ledger as a table (and as a downloadable .xlsx if you can), then the summary, then the "Unclear" list for me to resolve.
Constraints: use only figures in my documents. Do not round. Do not state any tax, allowance or deadline figures. If an input is missing, ask me before continuing.
Before you answer, check that the stream totals add up to the ledger total, that no row appears twice, and that every row has a source document. Report the result of that check.
Fill in: your stream list, the dates, the files, and anything you know is not income.
Reply to each Unclear row with a stream name. Do not let Claude settle them by guesswork, because the guesses are the part you cannot see later.
Add each month's exports to the same Project and run this.
Using the existing ledger in this Project, add the new documents I have uploaded for [MONTH_AND_YEAR]. Keep the same streams and column format. Show only the new rows, flag any that look like duplicates of earlier rows, update the one-page summary, and list any Expected items that have now been received or are overdue by more than [NUMBER_OF_DAYS] days. If anything is ambiguous, ask me first.
Swapping the categories for your own life is a matter of editing one line, [YOUR_STREAM_LIST]. If you are an employee with a small side income, use three streams: Salary, Side income, Other. If you are freelance, split by client type rather than by individual client. A stream deserves its own row once you would want to know whether it is growing, not just that it exists. If you cannot decide, run the prompt below once and let Claude propose a list that you then approve.
Here are descriptions of how I earn money: [DESCRIBE_EACH_SOURCE_IN_A_SENTENCE]. Propose a list of between four and eight income streams that covers all of it without overlap, say which of my sources goes in each, and name anything that does not belong in income at all. Ask me questions if my descriptions are too thin.
The trap is treating the ledger as your tax position. GOV.UK describes a £1,000 trading allowance and a £1,000 property allowance per tax year. If your trading income is over £1,000 you should register for Self Assessment, and you cannot claim the allowance and actual expenses against the same income. Whether any of that applies to you depends on facts the ledger does not contain. Note also that the registration deadline for the 2025 to 2026 tax year is 5 October 2026, with online returns and payment due by 31 January 2027. If you think you may need to register, check the GOV.UK pages today rather than waiting for the monthly update.