How to Manage Jobs, Invoices and Expenses as a UK Sole Trader

In short: keep one record for each customer, move every job through the same few stages, invoice when the work is finished, check what's been paid once a week, and record business expenses when you spend the money rather than at the end of the year. That's also most of what HMRC expects you to keep as a sole trader.

Below we go through each of those, then follow one job from the first enquiry to the money arriving in the bank. This is general guidance, not tax or legal advice. If you're unsure about your own situation, speak to an accountant or check HMRC's guidance on GOV.UK, which is linked throughout.

Why admin gets on top of sole traders

When you work for yourself, nobody else is going to send the invoice. And after a day on the tools, it's the last thing you feel like doing. Paid work comes first, so the admin gets pushed into evenings and weekends.

The difficulty is keeping track of everything when customer details, jobs, invoices and receipts are all stored in different places. Customer details end up spread across texts, WhatsApp, email and your call log. Jobs live in a diary or in your head, which is fine until a busy week. Invoices go out late because nobody wants to write one at 9pm, and late invoices tend to get paid late. Meanwhile receipts fade in the van door, and nobody is keeping an eye on who still owes you.

How to organise customer information

A customer record holds the details you need to contact someone, find their property and remember what you've done for them. Set one up the first time someone gets in touch, even before any work is agreed.

What to record for each customer

• Their name, and the business name if they're a company, letting agent or landlord.
• Phone number and email address. You'll need the email for sending invoices.
• The billing address, and the job address if it's different, which is common with landlords and agents.
• Notes on access, parking, pets and the best time to call, plus what's actually there: the boiler model, the consumer unit, the paint colour.
• How they found you, so you can see whether work is coming from recommendations, your website or a directory listing.

Keep the job history with the customer

Link each job and invoice to the customer it belongs to. When someone rings and says "you did our bathroom a couple of years ago", you can see what you did, what you charged and when, without scrolling back through old messages.

Look after the data

Customer details are personal information, so UK data protection law applies. Only keep what you need for the work, store it somewhere secure rather than on loose paper in the van, and don't use it for things the customer wouldn't expect. The ICO's advice for small organisations covers the basics.

How to keep track of jobs

The simplest way to track jobs is to give each one a status and move it along as the work progresses. Three stages are enough for most sole traders:

The last column is the one that costs people money. If a finished job hasn't been invoiced, you won't get paid for it until it is, so look over your completed jobs regularly and make sure each one has an invoice.

For each job, note the customer and job address, a short description such as "Replace kitchen mixer tap" or "Repaint hallway, stairs and landing", the agreed price or how you're charging (fixed price, day rate or hourly), the date booked and the date finished. Add any materials you buy for it, and any extra work the customer agrees to along the way. That last one is easy to forget by the time you write the invoice.

Recurring work

If you do regular rounds, such as window cleaning or garden maintenance, treat each visit as its own job or keep a log of visits for each customer. Either way, you should be able to see which visits have been invoiced and paid, especially if customers pay monthly or in arrears.

How to create and organise invoices

An invoice is a written request for payment. It sets out what you did, how much the customer owes and how to pay you, and it's also one of your main records of income.

What a UK invoice must include

According to GOV.UK's guidance on invoices, an invoice should include:

• a unique invoice number
• your name, address and contact details
• the customer's name (or company name) and address
• a clear description of what you're charging for
• the date the work was done (the supply date)
• the date of the invoice
• the amount being charged
• the VAT amount, if you're VAT registered
• the total amount owed

As a sole trader, you need to show your own name as well as any business name you trade under, such as "Sam Taylor trading as Taylor Plumbing". If you use a business name, you also need to include an address where legal documents can be delivered to you.

If you're VAT registered, there are extra rules about what your invoices must show. See HMRC's VAT guide or ask your accountant.

It's also worth adding your payment terms, an actual due date (clearer than "14 days"), and your bank details with a request to use the invoice number as the payment reference. That reference makes matching payments much quicker later on.

For the full requirements, a worked example and what changes once you're VAT registered, see our guide tohow to invoice as a sole trader.

Number invoices in order and never reuse a number

Use a simple sequence like INV-0001, INV-0002 and so on, and use each number once. If you make a mistake, don't edit an invoice you've already sent. Cancel it or issue a correction, then send a new one. An unbroken sequence makes it obvious if anything is missing.

Send it while the job is fresh

If you can, send the invoice before you leave site, or that evening once you're home, while the details are fresh and the customer is pleased with the work. Saving invoices up for the end of the month just delays your money.

Keep a copy of every invoice

Store a copy of each invoice you send, linked to the customer and the job. Sales invoices are part of the proof of income HMRC expects you to keep.

How to track payments and spot outstanding invoices

An outstanding invoice is one that's been sent but not yet paid in full. An overdue invoice is an outstanding invoice whose due date has passed.

To know where you stand, record three things against every invoice: the amount, the due date and whether it's been paid, with the date and how much. That's enough to see who owes you money and which invoices are late.

A simple weekly payment check

Pick the same time each week, such as Friday afternoon, and work through this:

1. Open your banking app and look at payments received since your last check.
2. Match each payment to an invoice, using the reference and the amount.
3. Mark those invoices as paid, with the date and amount received.
4. List any invoices that are still unpaid and past their due date.
5. Send a polite reminder for each overdue invoice.

While you're at it, check that every job you finished that week has been invoiced. Once it's a habit it's a quick job, and much easier than working out who's paid in January.

Part payments and deposits

If a customer pays a deposit or pays in instalments, record each payment against the invoice and keep track of the balance. Don't mark the invoice as paid until the full amount has arrived.

Chasing late payment

A lot of customers simply forget, so start with a friendly nudge on or just after the due date, giving the invoice number, the amount and your bank details. If a week passes with nothing, it's worth picking up the phone rather than sending another message. If it's still unpaid after that, send a firmer written reminder saying what you'll do next.

If you work for other businesses, for example a builder subcontracting to a main contractor or a letting agent, the law gives you extra rights. If no payment date was agreed, a business payment is usually late 30 days after the customer receives your invoice or the work is done, whichever is later, and you can generally claim statutory interest and fixed debt recovery costs. See late commercial payments on GOV.UK. These rules don't apply to work for private householders.

If you can't resolve a dispute, GOV.UK explains how to make a court claim for money.

How to record and organise business expenses

A business expense is money you spend to run your business, such as materials, fuel or insurance. As a sole trader, you pay tax on your profit, which is your income minus allowable expenses, so any allowable expense you don't record means paying more tax than you need to.

Common allowable expenses for tradespeople

GOV.UK lists the types of allowable expenses for self-employed people. For trades, the most common are:

• materials and parts used on jobs, such as pipe, cable, paint, plants, timber and fixings
• vehicle and travel costs for business journeys, such as fuel, insurance, repairs, servicing, parking and tolls (you may be able to use flat-rate simplified expenses for vehicles instead of working out actual costs)
• tools and equipment, although how these are treated can depend on the item and your accounting method, so check before claiming larger purchases
• uniforms and protective clothing such as safety boots and hi-vis, but not everyday clothes, even if you only wear them for work
• insurance, such as public liability insurance
• the business share of your phone and internet
• advertising, such as your website, directory listings, flyers and van signwriting
• trade body memberships, and training courses that keep your existing skills up to date
• financial costs, such as business bank charges

If something is used for both business and personal reasons, such as your phone or a van you also use at weekends, you can only claim the business part.

How to record an expense

For each expense, note the date, the supplier, what it was for, the amount (and the VAT, if you're VAT registered), a category such as materials, vehicle or tools, and the job it was for if there was one. Linking materials to jobs also shows you what each job really made.

Keep the receipt or invoice as proof. Paper till receipts can fade quickly, so take a clear photo as soon as you get one, ideally before you've left the car park.

Example: one job from enquiry to payment

Sam is a made-up self-employed plumber who isn't VAT registered. The names and figures are illustrative.

1. The enquiry (Monday)

Mrs Ahmed messages Sam: a radiator in her back bedroom is leaking and she'd like it replaced. Before replying with a time to look at it, Sam creates a customer record with her name, phone number, email, address and a note: "Back bedroom radiator leaking, wants replacement. Found us via neighbour."

2. Agreeing the price (Tuesday)

Sam visits, measures up and agrees a fixed price of £310 including the new radiator and valves. He confirms the price and his 14-day payment terms by email, so they both have a record of what was agreed, and books the job for Thursday at 9am. The job is now upcoming.

3. Doing the work (Thursday)

On the way, Sam picks up the radiator and valves from the merchant for £96.40. He photographs the receipt in the van and records it as a materials expense against Mrs Ahmed's job. The job is in progress until the new radiator is fitted and tested, then he marks it completed and adds the radiator size and model to her notes.

4. Invoicing (Thursday evening)

That evening Sam sends invoice INV-0047 for £310, due in 14 days, with his bank details and a note asking Mrs Ahmed to use INV-0047 as the reference.

5. Tracking payment (two weeks later)

In his weekly payment check, Sam sees INV-0047 is a day past its due date with nothing in his bank account. He sends a short, friendly reminder with the amount and his bank details.

6. Getting paid

Two days later, £310 arrives with the reference INV-0047. Sam marks the invoice as paid with the date received, and the job record now shows the whole picture:

At tax time, the income, the materials cost and the receipt are already there.

Practical tips for spending less time on paperwork

Most of the time saving comes from doing things as they happen. Adding a customer or logging an expense takes a minute on the day, and a lot longer when you're trying to remember it weeks later. A few other habits help too.

• Put your payment terms on the written price, so the invoice doesn't come as a surprise.
• On bigger jobs where you're buying materials up front, ask for a deposit before you order, and record it against the job.
• Photograph the boiler data plate, fuse board or paint tin label and add it to the customer's notes. Next time they ring, you'll know what's there.
• Save standard wording for invoice notes, payment terms and reminders, so you aren't writing them from scratch each time.
• Keep business money separate. Sole traders don't legally have to have a business bank account, but keeping business and personal money apart makes your records much easier to keep and check. Ask your bank which type of account you can use for business.
• Don't leave it all for January. Up-to-date records make your Self Assessment return quicker, and you won't be paying your accountant to sort through a carrier bag of receipts.

Paper, spreadsheet or app?

A duplicate invoice book and a paper diary are cheap and work fine until you need to find what you charged someone 18 months ago, or work out which of last month's invoices are still unpaid. Paper is also easy to lose and impossible to search.

Spreadsheets are flexible and cost little or nothing, but you have to set them up and keep them in order yourself, and they're awkward to update on a phone while you're on site.

Job and admin apps are built for this kind of work, usually run on your phone, and link customers, jobs, invoices and payments for you. They do cost a monthly fee, so pick one that covers what you need rather than paying for features you won't use. Accounting software is a different thing, built for bookkeeping and tax. Some sole traders use it alongside a job or admin app, often because their accountant recommends it.

If your income from self-employment and property is high enough, Making Tax Digital for Income Tax means you'll need to keep digital records and send quarterly updates to HMRC using compatible software. Check whether it applies to you before choosing a system (see the FAQ below).

Where GoWorkr fits

GoWorkr is a business admin app for UK sole traders and tradespeople, available now on the App Store, and it's one way to do this from your phone. It keeps customers, jobs, invoices, payments and expenses together, and you can ask its AI assistant things like "Who owes me money?" or tell it to log a job.

It's an admin app, not accounting software. GoWorkr doesn't file tax returns, doesn't submit Making Tax Digital updates to HMRC, and doesn't take card payments from your customers. You'll still need to complete your Self Assessment yourself or with an accountant. See how GoWorkr works.

Frequently asked questions

What records do I need to keep as a sole trader?

Records of all your sales and income and all your business expenses, plus VAT records if you're VAT registered and PAYE records if you employ anyone. You should keep records of your personal income too. Proof includes receipts, bank statements and copies of your sales invoices. See what records to keep on GOV.UK.

How long do I have to keep business records?

At least 5 years after the 31 January Self Assessment deadline for the tax year the records relate to. For example, records for the 2025 to 2026 tax year, with an online return due by 31 January 2027, must be kept until at least 31 January 2032. See how long to keep your records on GOV.UK.

What does an invoice need to include?

A unique number, your name and contact details, the customer's details, what the work was, the dates, the amount and any VAT. The full GOV.UK list is in the invoices section above.

Do I need a separate business bank account?

Not legally, if you're a sole trader. A separate account does make it much easier to tell business and personal money apart, and some banks don't let you use a personal account for business, so check with yours.

When is an invoice overdue?

When it hasn't been paid by the due date you set. For private customers that's whatever you agreed, so always put a due date on your invoices. For work for other businesses, if no date was agreed, payment is usually late 30 days after they receive the invoice or the work is done, whichever is later.

Does Making Tax Digital affect how I keep records?

It might. Making Tax Digital for Income Tax applies to sole traders whose qualifying income (self-employment and property income combined, before expenses) is over a threshold. It applies from 6 April 2026 if that income was over £50,000 in the 2024 to 2025 tax year, from 6 April 2027 if it's over £30,000 in 2025 to 2026, and from 6 April 2028 if it's over £20,000 in 2026 to 2027. If it applies to you, you'll need compatible software to keep digital records and send updates to HMRC. Check if you need to use Making Tax Digital for Income Tax.

Can I just use a spreadsheet?

Yes, plenty of sole traders do, and it's fine for keeping customer, job and invoice records. A spreadsheet on its own can't send Making Tax Digital updates to HMRC, though, so if MTD applies to you, you'll need software that can, such as bridging software that works with your spreadsheet.