Choosing an Invoice App in NZ: A Checklist for Sole Traders

Short answer: A good invoice app for a New Zealand sole trader produces invoices that meet Inland Revenue’s taxable supply information rules, with 15% GST shown correctly if you are registered and no GST at all if you are not. It also turns an accepted quote into an invoice without retyping, keeps receipts with the job, shows who still owes you, and holds records you can still open in seven years. After that, the real choices are where your data lives (a cloud account or your own phone) and how you pay (a monthly subscription or a one-off price).

Inland Revenue’s rules are about the records you keep, not the tool you keep them in, so the right app is simply the one that keeps those records complete with the least effort. The rules referred to below are those in force for the 2027 tax year (1 April 2026 – 31 March 2027). If you only need the document itself, the NZ invoice template has GST and non-GST layouts, and how to invoice as a contractor in NZ covers the whole process from quote to payment.

What should an invoice app do for a NZ sole trader?

It should cover the money side of a job from the first quote to the last receipt, so nothing has to be copied between tools. These are the jobs to test it against:

Job	What to look for
Quote	A quote that converts to an invoice in one step once the customer accepts
Invoice	GST-correct PDF invoices with your details, numbering and payment terms
Get paid	A clear list of unpaid and overdue invoices, and help writing reminders
Expenses	Receipt capture and expense records, kept with the job they belong to
Mileage	A log of business trips if you drive for work; see IRD mileage rates
Year end	Exports or reports your accountant can use for your IR3 and GST returns

An app that does only the invoice leaves you running a second system for receipts and a third for who owes you. That is where records go missing, and a missing receipt is a deduction you do not claim. Self-employed expenses and receipts lists what you can claim.

Will it produce GST-correct invoices for New Zealand?

Check before you send a single invoice, because the rules depend on the value of the sale. Inland Revenue’s requirements for taxable supply information come in three tiers:

Sale value (incl GST)	What a GST-registered seller’s invoice must show
$200 or less	Nothing has to be given to the buyer, but you (and a GST-registered buyer) must keep a record
Over $200 to $1,000	Your name or trade name, GST number, date, description, and either the GST-exclusive amount, GST and total, or a GST-inclusive total stating GST is included
Over $1,000	All of the above, plus the buyer’s name and one identifier (address, phone, email, NZBN, trading name or website) if they are GST registered

So the app must let you:

• Set GST at 15% and label it GST, not “tax” or “VAT”. Inland Revenue’s GST page confirms the rate.
• Show your GST number on every invoice once you are registered.
• Switch GST off entirely if you are not registered. You must register once turnover reaches $60,000 in 12 months, under Inland Revenue’s registering for GST rules, and until then you must not charge GST. What GST is in NZ covers the basics.
• Add buyer details for larger jobs with registered customers.
• Price GST-inclusive or GST-exclusive and get the arithmetic right either way. A $1,150 GST-inclusive total should show $150 of GST, not $172.50. How to calculate GST shows the sums.

A quick test: before you commit, create one invoice over $1,000 to a GST-registered business and check every line against the table above.

Can it turn a quote into an invoice?

For trades and project work, this saves the most time. You write the quote once (scope, materials, labour, how long the price holds) and when the customer accepts, the same lines become the invoice. Nothing is retyped, so nothing is mistyped.

Look for three things:

• Quote and invoice linked to one job, so you can see what you quoted against what you billed.
• Easy changes, for variations agreed on site, before the quote becomes the invoice.
• Clear wording on whether the price is fixed or an estimate, and the date it is valid until.

If you rarely quote, this matters less. If most jobs start with a quote, it is the feature you will use most.

Where does the app keep your records, and does it matter?

Yes, because invoices and receipts are tax records. Inland Revenue’s record keeping guidance is to keep them, including electronic records, for at least 7 tax years, in a form that can be read. If records are stored offshore, which includes cloud storage, either you or your cloud service provider needs Inland Revenue’s approval.

Apps fall into two groups:

	Cloud app with an account	On-device app
Where data lives	The provider’s servers, synced to your devices	Only on your phone
Sign-up	Account and login	None
Use on several devices or share with an accountant	Usually yes	No; you export and send
Works without internet	Varies	Yes
Backups	Handled by the provider	Your responsibility
If you stop paying or the service closes	Check how you would export your records	Records stay on the phone

Neither is right for everyone. Most cloud invoicing apps require an account and sync your data to their servers, which suits you if you want access from a laptop or want your accountant to log in. An on-device app suits you if you work from your phone and would rather your customer list and income were not held by anyone else. The trade-off is that keeping copies, such as the PDFs you send and any exports, is up to you.

What does an invoice app cost?

Most apps use one of three pricing models, and the comparison that matters is the cost over the years you will use it, not the first month.

• Free tier with limits: common restrictions are a cap on invoices per month, the app’s branding on your invoices, or locked features such as exports.
• Monthly or annual subscription fee: common with cloud apps. Over seven years of record keeping, a small monthly fee adds up, and you should check what happens to access to your records if you stop paying.
• One-off purchase: you pay once and keep using it.

An app you use for the business is a business expense, so the cost reduces your taxable profit. Price is still a weaker reason to choose than whether you will actually record every receipt in it.

Do I need accounting software instead of an invoice app?

Only if you need what accounting software adds: bank feeds, full ledgers, or preparing and filing GST returns from the software. Inland Revenue lets you file a GST return in myIR or through accounting software that connects to it; an invoice app keeps the invoices and receipts the return is built from.

Your situation	What usually fits
Occasional invoices, not GST registered	A free online invoice generator or a template
Regular jobs, quotes and receipts on the go	An invoice and quote app on your phone
GST registered, many transactions, want bank reconciliation	Accounting software, or an app plus an accountant
You hand everything to an accountant at year end	Whatever produces the exports your accountant asks for

If you only send the odd invoice, the free invoice generator builds a PDF in your browser with no sign-up. Set the tax rate to 15% if you are registered, and check the result against the table above. It does not keep records or track who owes you, so save every PDF you send.

Choosing an on-device app, and where does Keel fit?

Keel: Invoice Maker & Receipts is an iPhone app by Ilura Technology OÜ in the on-device group. You create quotes, and an accepted quote becomes the invoice in one tap. Each job keeps its quote, receipts, expenses and invoice together, alongside your customers, PDF invoices, business mileage records, and “who owes you”, which prepares reminder drafts you review and send yourself; nothing is ever sent automatically. You can also type what you want done into the dock. There is no account, no bank connection and no cloud sync; records stay on your iPhone, and the App Store privacy label reads “Data Not Collected”.

It is free to use with no invoice limit; free invoices carry a small “Made with Keel” footer. Keel Lifetime is a one-time purchase of $249.99 USD (the App Store shows your local price) that adds custom branding, your signature, premium templates and accountant-ready exports and advanced reports.

What it is not: accounting software. Keel does not file GST returns, does not connect to Inland Revenue or your bank, and does not work out the tax you owe. As with any app, check that the invoices it produces meet the GST checklist above for your situation. Keel on the App Store.

Frequently asked questions

What is the best invoice app for sole traders in NZ? The best one is the app that produces GST-correct invoices for your situation and that you will keep up to date. Check that it handles 15% GST and your GST number (or no GST if you are not registered), converts quotes to invoices, keeps receipts with the job and shows who owes you. Then choose between a cloud account and on-device storage, and between a subscription and a one-off price.

Is there a free invoice app in NZ? Yes, several invoicing apps have free versions, but check the limits before relying on one. Common restrictions are a monthly cap on invoices, the app’s branding on your invoices and locked exports. Also check whether you can still get your records out if you stop using it, because you must keep them for at least seven tax years.

Can I use a free online invoice generator instead of an app? Yes, for occasional invoices. A generator makes a PDF, but it does not remember who owes you, keep your receipts or number invoices across the year, so you need your own system for those. Save every PDF you send, since invoices are records you must keep for at least seven tax years.

Do I need accounting software as a sole trader in NZ? No. Inland Revenue requires you to keep complete records of income and expenses, not to use any particular software. Many sole traders manage with an invoice app or templates plus an accountant at year end. Accounting software earns its cost when you want bank feeds, have many transactions or want to file GST returns directly from the software.

Can an invoice app file my GST return? Usually not. Simple invoice and quote apps keep the invoices and receipts your return is built from, but you file in myIR or through accounting software that connects to Inland Revenue. If you file GST yourself, make sure your app can show sales and expenses for the period, including GST, so you can fill in the return quickly.

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This article is general information, not tax advice. Consult a qualified New Zealand tax professional.