You did not become a plumber, sparky, or builder to do paperwork. But small business bookkeeping is the difference between a trade that quietly makes money and one that limps from invoice to invoice, panics at tax time, and never really knows if it is winning. The good news: you do not need an accounting degree or a fancy system. You need a minimum viable setup that keeps you out of trouble and tells you your numbers, run in twenty minutes a month.
This guide lays out exactly that system: separate your money, record every pound and euro that comes in and goes out, set tax aside as you earn it, keep your records for the years the law requires, reconcile what is paid against what is still owed, and review it once a month. We will also be straight with you about where Billr fits and where it does not, so you build the right toolkit instead of expecting one app to do everything.
Why bookkeeping matters even if you hate it
Three reasons, none of them optional. First, the tax authority expects accurate records, and "I lost the receipts" is not a defence when they ask. Second, you cannot price a job properly if you do not know what last year actually cost you. Third, cash flow kills more trades than bad workmanship: you can be busy and profitable on paper and still run out of money because you never separated the tax you owe from the cash in the account.
Bookkeeping is just the habit of writing down what happened with money so future-you, your accountant, and the taxman can all see the truth. Done little and often, it takes minutes. Left until the shoebox of receipts is overflowing, it becomes a weekend of misery and guesswork.
The six-part minimum viable bookkeeping system
Here is the whole system. Master these six and you are ahead of most one-van trades.
1. Separate business money from personal money
This is the foundation, and it is the one most people skip. Open a dedicated business bank account and run every job payment in and every business cost out through it. Stop paying for diesel with the same card you buy the weekly shop on.
Why it matters so much: when business and personal money mix, you cannot tell what the business earned or spent without untangling months of statements line by line. Keep them separate and your business account statement becomes a near-complete record of your trade by itself. Pay yourself by transferring a wage or a draw from the business account to your personal one, on a regular day, so even your own pay is a clean, traceable line.
2. Record all income
Every job you complete should produce an invoice, and every invoice is a line in your income record. This is the part Billr handles for you. When you turn tracked time into a professional invoice and mark it paid, you have created a dated, numbered record of money earned, with the client, the amount, the tax, and the payment method all captured.
The discipline is simple: no work goes unbilled, and no cash job goes unrecorded. A EUR 180 callout paid in cash is income exactly like a GBP 4,200 bathroom refit paid by card. If it is not on an invoice, it does not exist in your books, and undeclared cash is how decent trades end up in trouble they never planned for.
3. Record all expenses with receipts
Every cost of running the trade goes in the expense side, and every one needs a receipt or invoice to back it up. The big categories for a tradesperson:
- Materials from merchants and suppliers, including the three top-up runs you forgot about.
- Fuel and vehicle costs: diesel, servicing, insurance, the van lease.
- Tools and equipment, from a GBP 12 hole saw to a GBP 900 SDS drill.
- Subcontractors: the plasterer you brought in for a day, the sparky who signed off the board.
- Overheads: phone, insurance, software, accountant fees, advertising, workwear.
Snap a photo of every receipt the moment it lands in your hand, before it turns to pulp in the van footwell. Most tax authorities now accept a clear digital photo, so a folder on your phone beats a glovebox full of faded paper. The rule of thumb: if you would not be embarrassed to show it to an inspector, it is a record; if it is a guess, it is a liability.
4. Set aside money for tax and VAT as you go
The single most painful mistake in any small trade is spending money that was never yours. When a client pays you, part of that payment belongs to the taxman: income tax on your profit and, if you are VAT registered, the VAT you charged on top of your price.
Do not wait until the bill arrives. Every time you get paid, move a percentage straight into a separate tax savings account. A simple starting rule for many sole traders is to park 25-30% of profit for income tax, and if you are VAT registered, the full VAT element on top of that. On a GBP 4,200 invoice with 20% VAT, GBP 700 of that is VAT you are merely holding for the government, not income. Treat it as theirs from the second it lands and you will never face a tax bill you cannot pay.
5. Keep your records for the required number of years
You cannot bin last year's invoices when the new year starts. Tax authorities require you to keep records for a set number of years in case they check, and the period varies by country: it is commonly five to seven years, and longer in some places. As a safe default, keep everything for at least seven years unless your accountant tells you your country needs less.
That means invoices, receipts, bank statements, and your records of what was paid and when. Digital copies are fine in most jurisdictions and far easier to keep than paper. From Billr you can export your earnings and work reports and save a PDF of each invoice, so your income side is archived and searchable rather than scattered.
6. Reconcile paid vs outstanding, and review monthly
Reconciling means matching your records against reality: which invoices have actually been paid, and which are still outstanding. An invoice marked paid in your books but never actually received is a hole in your accounts and your cash flow.
Billr flags this for you. Every invoice carries a status, overdue invoices are flagged automatically, and the dashboard shows your total balance due. Once a month, sit down and do the loop: confirm every "paid" invoice actually hit the business account, chase anything overdue, file the month's receipts, move the tax money across, and glance at your reports. Twenty minutes, once a month, and you are never more than thirty days from knowing exactly where you stand.
Where Billr fits, and where it does not
This is the honest part, because matching the right tool to the right job is itself good bookkeeping. Billr is your invoicing and income record. It is the income side of your books, done properly:
- Tracked time becomes professional invoices, so billable work is captured at the rate you applied.
- Invoices marked paid or unpaid give you a clean, dated income ledger with overdue flagging.
- Earnings and work reports you can export show revenue by client and period for your accountant or your records.
- Payment details are recorded: when an invoice was paid, the provider used, the amount and currency received, and the reference IDs, which is exactly what you reconcile against your bank.
What Billr is not is a full accounting package, and pretending otherwise would set you up to fail. Billr does not keep an expense ledger, it does not connect to your bank to auto-reconcile a bank feed, and it does not file your tax return. For the expense side, the bank reconciliation, and the filing, you still need a dedicated accounting tool or an accountant.
The clean division of labour: Billr owns "what did I earn and has it been paid," and feeds that clean income data into whatever handles "what did I spend and what do I owe the taxman." Get those two halves talking and your bookkeeping is genuinely under control. If you are still firming up your prices, costing the work right starts with knowing how to set your hourly rate so the income side is worth recording in the first place.
A simple monthly routine
Put a recurring twenty-minute slot in your diary, last Friday of the month, and run this checklist every time:
- Invoice everything outstanding. Turn the month's tracked time into invoices so no work slips through unbilled.
- Reconcile. Check each "paid" invoice actually landed in the business account, and flag anything overdue to chase. Clear payment terms make this far easier, so it helps to understand how invoice payment terms work.
- File expenses. Make sure every receipt for the month is photographed and saved into your expense tool.
- Move the tax money. Transfer your tax and VAT percentage into the separate savings account.
- Review the numbers. Glance at your earnings report: what did you bring in, who owes you, how does it compare to last month.
FAQ
Do I need an accountant if I do my own bookkeeping?
For most trades, yes, at least once a year. Good day-to-day bookkeeping (separating money, recording income and expenses, saving for tax) makes the accountant's job cheaper and faster, but a professional will handle your tax return, catch deductions you missed, and keep you compliant. Think of your bookkeeping as feeding the accountant clean data, not replacing them.
Can Billr do my full bookkeeping?
No, and it does not claim to. Billr handles your income side: invoicing from tracked time, marking invoices paid or unpaid, recording payment details, and exporting earnings and work reports. It does not keep an expense ledger, reconcile a bank feed, or file taxes. Pair it with a dedicated accounting tool or an accountant for the expense and filing side.
How much should I set aside for tax?
It depends on your country and your profit, but a common safe starting point for sole traders is 25-30% of profit for income tax, plus the full VAT element if you are VAT registered. Ask your accountant for the right percentage for your situation, then move it the moment you get paid so it is never spent by accident.
How long do I need to keep my records?
It varies by country, commonly five to seven years and sometimes longer. A safe default is to keep everything for at least seven years: invoices, receipts, bank statements, and payment records. Digital copies are accepted in most places, so archive PDFs and photos rather than hoarding paper.
What is the simplest way to start if I am behind?
Open a dedicated business account today and run everything through it from now on. You will not fix the past overnight, but a clean account going forward gives you a near-complete record without extra effort. Then invoice everything, save every receipt, and book a session with an accountant to tidy up the backlog.
Key takeaways
- Separate business and personal money with a dedicated business account so your statement is a near-complete record.
- Record all income (your invoices) and all expenses (materials, fuel, tools, subs) with receipts, photographed straight away.
- Set aside tax and VAT every time you get paid, into a separate account, so the taxman's share is never spent.
- Keep records for the required number of years (a safe default is seven) and reconcile paid vs outstanding monthly.
- Billr is your income and invoicing record, not a full accounting package: it has no expense ledger, no bank reconciliation, and no tax filing, so pair it with an accounting tool or accountant.
Bookkeeping does not have to be a weekend lost to a shoebox of receipts. Build the minimum viable system, run it twenty minutes a month, and let Billr handle the income side cleanly. See how Billr turns your tracked time into invoices and a tidy income record, then hand that clean data to your accountant and stop dreading tax time.