Guide · Invoicing · Sole traders

Best invoicing app for UK sole traders (2026)

An honest comparison. We cover the main options — paid and free — with clear guidance on which suits which situation. No one app is best for everyone.

Written by the WrkGenie team

WrkGenie is a UK-built job management platform for sole traders and small service businesses. Our guides are written from the practical questions we hear from real customers — not for SEO purposes first.

We aim to keep guides factually accurate and up to date. If you spot something out of date or incorrect, let us know.

About WrkGenie · All guides

What a sole trader actually needs from an invoicing app

The answer isn't the same as what a 10-person business needs. Before comparing tools, it's worth being clear about what matters for a one-person operation.

  • Creating invoices quickly on the go — most solo service providers invoice from a phone, often immediately after the job or while still on site. A slow or desktop-first interface kills adoption.
  • Knowing who has and hasn't paid— chasing payment is a major time sink. A clear "outstanding" view removes the need to track this manually.
  • HMRC-compliant records for self-assessment — sole traders need to keep records of income for the tax year. An invoicing app that logs everything in one place makes year-end straightforward (or less painful).
  • Quoting that connects to invoicing — if your work starts with a quote, having the invoice flow from that quote (rather than retyping) saves time and reduces mistakes.
  • VAT handling if approaching the threshold— the UK VAT registration threshold is £90,000. If you're getting near it, your invoicing app needs to handle VAT invoices and ideally help you track where you are against the threshold.
  • Recurring invoices for regular customers — if you have customers on a regular schedule (weekly cleaners, monthly maintenance), automating their invoices removes a recurring admin task.

The main options compared

WrkGenie

UK sole traders + trades

Built for UK service businesses — primarily tradespeople and sole traders who do field work. Invoicing is connected directly to quoting and job management, which means the entire workflow from "customer enquiry" to "invoice paid" lives in one place.

What it does well:

  • Quote → job → invoice flow with no retyping
  • VAT-compliant invoices (including reverse charge for CIS builders)
  • Recurring invoicing for regular maintenance customers
  • Mobile-first — built for use between jobs, not at a desk
  • Sequential invoice numbering (HMRC requirement)
  • Deposit invoicing for large jobs
  • Flat monthly fee — no per-user charges

Limitations:

  • Not a full accounting system — no bank reconciliation, payroll, or tax return filing
  • Aimed at service businesses, not product-based retail

Best for: UK sole traders and small trades businesses who need invoicing connected to job management, not standalone bookkeeping.

From £19.99/month.

FreeAgent

Designed for UK freelancers and small businesses. Includes invoicing, self-assessment tax estimation, and bank feeds. Popular with contractors and consultants who need basic accounting alongside invoicing.

What it does well:

  • Self-assessment tax estimation as you go
  • Bank feed integration (if you use a compatible bank)
  • Good for consultants and freelancers with straightforward invoicing
  • HMRC-recognised software for Making Tax Digital

Limitations:

  • No job management or scheduling — invoicing only
  • Can feel complex if you just want to send an invoice quickly
  • Monthly cost is higher than simple invoicing tools

Best for: Sole traders who want invoicing + basic self-assessment support, particularly consultants and freelancers rather than trades.

QuickBooks Self-Employed / QuickBooks Simple Start

QuickBooks Self-Employed is aimed at freelancers and the self-employed. It offers mileage tracking, basic invoicing, and self-assessment tax calculation. QuickBooks Simple Start is a step up with more accounting features.

What it does well:

  • Mileage tracking built in
  • Self-assessment tax estimate
  • HMRC Making Tax Digital compliant
  • Widely supported by UK accountants

Limitations:

  • No quoting, job tracking, or scheduling
  • Invoicing is basic — not designed for trades workflows
  • QuickBooks Self-Employed specifically lacks proper VAT invoice support
  • Per-user pricing on higher tiers adds up for small teams

Best for: Sole traders whose accountant uses QuickBooks and who want invoicing + self-assessment in one place. Not the right choice if you also need quoting or job tracking.

Xero

Xero is full accounting software — bank reconciliation, multi-currency, payroll add-on, detailed reporting. Very capable, but significantly more than most sole traders need or want to manage.

Limitations for sole traders:

  • Monthly cost is high for simple invoicing use
  • Steep learning curve if you just want to send invoices
  • No job management, scheduling, or quoting

Best for: Businesses with an accountant who requires Xero, or businesses that are scaling toward needing full accounts. Overkill for most one-person trades.

Free invoice generator or Word/Excel template

If you send 2–3 invoices a month, all for clearly scoped jobs with no quoting, and your customer base is small and reliable, a free invoice template or a tool like WrkGenie's free invoice generator is entirely adequate.

Where free breaks down:

  • No record of who has or hasn't paid
  • Manual tracking of invoice numbers
  • No recurring invoice automation
  • No quoting connection
  • Year-end records require manual compilation

Best for: Very low-volume invoicing where the business is genuinely simple. Use it until the admin overhead of manual tracking outweighs the cost of a paid tool.

Quick comparison

ToolInvoicingQuotingJob trackingAccounts
WrkGenie✓✓✓–
FreeAgent✓Basic–Basic
QuickBooks✓––✓
Xero✓––✓
Free toolsBasic–––

The invoicing habits that get sole traders paid faster

The tool you use matters less than when you invoice. Research consistently shows that invoices sent the same day as the work is completed are paid significantly faster than those sent days later.

  • Invoice the same day— while the job is fresh in the customer's mind and you're still on their doorstep (metaphorically). An invoicing app that works well on mobile makes this possible even for complex quotes.
  • State payment terms clearly— "Payment due within 14 days" on every invoice. Customers pay faster when they know the expectation. Under the Late Payment of Commercial Debts Act, you are also entitled to statutory interest on overdue B2B invoices.
  • Send a reminder before the due date — not a chase, just a courtesy reminder. WrkGenie can do this automatically.
  • Make payment easy— include a bank transfer reference, or offer card payment via an integrated link. The fewer steps between "invoice received" and "payment made," the faster it happens.
  • Use a deposit for large or unfamiliar jobs — a 25–50% deposit before starting work on anything significant protects your materials cost and reduces the risk of a dispute on the final invoice.

VAT and invoicing as a UK sole trader

If your turnover is below £90,000 in any rolling 12-month period, you are not required to register for VAT or charge it. Your invoices do not need to show VAT, and you should not add it.

If you are approaching the threshold, it is worth knowing what changes when you register:

  • All invoices must be VAT invoices with your VAT registration number
  • VAT must be shown as a separate line item
  • You file quarterly VAT returns with HMRC
  • You can reclaim VAT on business purchases (tools, materials, van costs)

If you work under the Construction Industry Scheme (CIS) as a subcontractor, your VAT invoicing has additional considerations — specifically the domestic reverse charge for most construction services. Use the VAT calculator for quick calculations, and check the UK invoicing guide for what must appear on a compliant invoice.

Pricing traps to avoid when choosing an app

  • Per-user pricing— some tools charge per user. If it's just you, this doesn't matter. If you add a part-time admin or a second operative later, the cost can jump significantly. Flat-fee tools are more predictable.
  • Annual contracts — some tools lock you in for 12 months. Look for month-to-month options, especially when evaluating.
  • Free tiers with invoice limits— some free tiers cap you at 5 or 10 invoices per month. Fine if you're genuinely low volume, but check before you scale.
  • Paying for features you don't need— payroll, multi-currency, inventory management. These are valuable for the right businesses. If none of them apply to you, you're subsidising features you'll never use.

Quick recommendation guide

You're a sole trader in a trade business (electrician, plumber, builder, cleaner, etc.)

→ WrkGenie. Invoicing connected to quoting and job tracking, built for mobile, flat fee.

You're a freelance consultant or contractor billing by time

→ FreeAgent or QuickBooks Self-Employed. Good tax estimation, simpler invoicing workflow.

Your accountant requires a specific tool

→ Use what they ask for. The accountant relationship is worth more than the tool preference.

You send fewer than 5 invoices a month and don't quote

→ Start with the free invoice generator. Switch when the admin overhead of manual tracking becomes obvious.

You're growing and need proper accounts

→ Xero or QuickBooks with an accountant. Overkill for most sole traders, but right once the business gets to a certain size.

Frequently asked questions

Do I need a paid invoicing app as a sole trader?

Not always. If you send fewer than 5 invoices a month and have simple, predictable pricing, a free tool or even a Word template might be sufficient. The case for a paid app gets stronger when you have recurring customers, quote before invoicing, need to track who has and hasn't paid, or are approaching the VAT threshold and need accurate records.

What does a UK-compliant sole trader invoice need to include?

Your name and address (or business name), the customer's name and address, a unique invoice number, the date, a description of the goods or services, the amount, and your payment terms. If you are VAT registered, you must also include your VAT number, the VAT rate applied, and the VAT amount shown separately.

Is QuickBooks or Xero overkill for a sole trader?

Often, yes. Both are built primarily for businesses that need double-entry bookkeeping, payroll, or multi-user accounting. Most sole traders use less than 20% of their features and find the interface overwhelming. If your accountant specifically asks you to use one, that's a valid reason. Otherwise, simpler tools are usually a better fit.

What's the difference between an invoicing app and accounting software?

An invoicing app focuses on creating, sending, and tracking invoices — and often includes quotes and job tracking. Accounting software does that plus bookkeeping, bank reconciliation, VAT returns, payroll, and financial reporting. Most sole traders need the former, not the latter, until the business reaches a scale where proper accounts are required.

What should I look for in an invoicing app for mobile use on site?

Mobile-first UI (not a desktop app squeezed into a phone), ability to create and send invoices without internet access (or at least on patchy 4G), quick line-item entry without lots of steps, and the ability to see outstanding invoices at a glance. Bonus: if the app also does quoting, you can send a quote on site and convert it to an invoice the same day.

Related tools

Related guides

Ready to run your business properly?

Start your free 14-day trial today. No setup hassle, no commitment — just see if it works for you.

Free for 14 days · then £19.99/month · cancel anytime

14-day free trial · Cancel anytime · No contracts