Free Profit and Loss Calculator for UK Self Employed (2026/27)

Understanding your profit and loss position is one of the most important things you can do as a self-employed person, yet most sole traders only find out their numbers when their accountant files their tax return. By then, it is too late to make decisions that could have reduced your bill.

This guide explains what a profit and loss statement is, how to calculate yours, and how Built For Small Business gives you a live P&L view throughout the year for free.

What is a profit and loss statement?

A profit and loss statement, often called a P&L or income statement, shows your income, costs, and resulting profit or loss over a specific period. For sole traders, the most relevant period is the tax year: 6 April to 5 April for UK businesses.

Your P&L answers three questions:

• How much did I earn?
• How much did I spend?
• How much did I actually make?

That third number, net profit, is what HMRC taxes you on.

How to calculate your profit and loss

The calculation has three layers:

Layer 1 — Gross income: Your total invoiced income for the tax year, every payment received from clients, plus any other business income such as cash sales, grants or interest.

Layer 2 — Gross profit: Gross income minus your allowable business expenses. This is your profit before payroll costs.

Gross Profit = Total Income − Business Expenses

Layer 3 — Net profit: Gross profit minus any staff or payroll costs. This is your taxable profit, the figure that goes on your Self Assessment return.

Net Profit = Gross Profit − Payroll Costs

A worked example:

HMRC taxes you on £34,500, not on the £55,000 you earned.

What counts as income?

For your P&L, income includes:

• Invoice income — all paid invoices for the tax year, based on invoice date, not payment date (unless you use cash accounting)
• Cash sales — income not invoiced through your system
• Grants — SEISS payments, local authority grants, other business grants
• Bank interest on business accounts
• Other business income — any other revenue connected to your trade

Outstanding invoices, money owed but not yet paid, should also be tracked separately. They represent income you have earned but not yet received, which affects your cash flow even if it does not change your tax position under accrual accounting.

What counts as expenses?

Allowable expensesreduce your taxable profit. HMRC's main categories are:

• Office costs — stationery, software, broadband, phone
• Travel — mileage at 45p/mile, public transport, parking
• Premises — rent, rates, utilities for business premises
• Staff costs — wages, employer NI, pension contributions
• Marketing — website, advertising, promotional materials
• Professional fees — accountant, solicitor, insurance
• Training — courses and qualifications, updating existing skills
• Financial costs — bank charges, loan interest, business insurance

The lower your total allowable expenses, the higher your taxable profit and the more tax you pay. Recording every legitimate expense throughout the year is the most straightforward way to reduce your bill legally.

Why your P&L matters beyond tax

Your profit and loss statement is not just for HMRC. It is useful in several other situations:

Mortgage applications. Lenders assess self-employed applicants on their net profit as shown on their SA302. A clearly presented P&L alongside your tax return strengthens your application and can explain year-on-year changes in your income.

Business loans and grants. Banks and grant providers want to see that your business is financially viable. A P&L showing consistent profit or clear growth gives them confidence.

Business planning. Seeing your income and expenses broken down by month tells you which months are strong and which are lean, helping you plan cash flow, manage tax savings, and make better spending decisions.

Accountant efficiency. The cleaner and more complete your P&L records, the less time your accountant spends reconstructing your finances, and the lower your accountancy bill.

The tax estimate connection

Your net profit feeds directly into your tax calculation. For UK sole traders, tax is made up of:

• Income Tax — 20% on profit between £12,570 and £50,270, 40% above that
• Class 2 NI — £3.65 per week if profit exceeds £6,725
• Class 4 NI — 6% on profit between £12,570 and £50,270, 2% above

Using the example above — net profit of £34,500:

Knowing this figure in April rather than January gives you 9 months to save for it, rather than scrambling to find the cash in the same month as your bill arrives.

How Built For Small Business generates your P&L automatically

Built For Small Business tracks your invoices, expenses and payroll throughout the year. Your P&L report is generated automatically from that data, broken down by tax year, with no manual calculation required.

What your BFSB P&L shows:

• Total invoice income — all paid invoices for the selected tax year
• Additional income — cash sales, grants or other income you add manually
• Expenses by HMRC category — with a breakdown of every category and its percentage of total costs
• Payroll costs — if you run payroll through BFSB
• Monthly income vs expenses chart — so you can see your financial position month by month
• Net profit — your taxable profit for the year
• Tax estimate — based on current HMRC rates for your UK nation (England, Scotland, Wales or Northern Ireland)
• Monthly set aside — how much to put away each month to cover your estimated bill

Business plan users can also download the P&L as a PDF, ready to share with an accountant, a mortgage adviser, or a bank.

How to use your P&L to reduce your tax bill

Check your expense categories. Are there legitimate expenses you have not recorded? Common ones missed include mileage, home working costs, software subscriptions, professional memberships and training.

Look at outstanding invoices. A high outstanding balance means money you have earned but have not collected. Chasing overdue invoices improves your cash position and means your income matches your effort.

Plan large purchases before April. If you are considering buying equipment, doing it before 5 April means you can claim the Annual Investment Allowance in the current tax year — reducing your taxable profit immediately.

Make pension contributions before 5 April. Pension contributions reduce your taxable income. If your P&L shows a higher profit than expected, a pension contribution before the tax year ends reduces both your income tax and Class 4 NI.

Frequently Asked Questions

Do I need an accountant to produce a P&L?
Not if you keep good records throughout the year. A P&L generated from your invoice and expense records is straightforward to produce. An accountant adds value in interpreting it, identifying missed expenses, and ensuring your tax return is filed correctly.

What is the difference between profit and cash flow?
Profit is what you have earned minus what you have spent. Cash flow is what has actually moved through your bank account. An invoice raised in March might not be paid until May; it appears in your profit for the March tax year, but in your cash flow for May. Understanding both is important for managing your business.

How often should I review my P&L?
Monthly is ideal. A monthly review takes minutes if your records are up to date and tells you whether you are on track, or whether you need to adjust your spending, chase invoices, or increase your set-aside for tax.

Can I share my P&L with my accountant directly?
Yes, Business plan users on BFSB can download the P&L as a PDF and share it directly. Free users can share their expense report via a secure link which their accountant can view without creating an account.

This article is for informational purposes only and does not constitute financial or tax advice. Figures are based on 2026/27 HMRC rates for England. Scottish rates differ. Always consult a qualified accountant for advice specific to your circumstances.