The mistakes hiding in your invoicing process

Most NZ trade businesses don't lose money because of bad workmanship - they lose it because of bad admin. Invoicing is where a disproportionate amount of that money disappears: in late payments that could have been prevented, in invoices that get lost or disputed, and in time spent chasing money that should never have been overdue in the first place.

Here are the five most common invoicing mistakes - and exactly how to fix them.

Mistake 1: Sending invoices late

Every day you delay invoicing is a day later you get paid. This sounds simple, but most tradies don't invoice same-day. They invoice when they get back to the office, when they have time to write it up, when they remember - often days or even a week after the work is done.

Why it matters more than you think:

A $5,000 invoice sent 5 days late, collected on 14-day terms, won't clear until nearly 3 weeks after the job. That's 3 weeks of your capital tied up in someone else's account.
Delayed invoicing signals that the debt isn't urgent - clients treat it accordingly.
The longer after job completion, the higher the chance of a dispute. "The work was done months ago, I thought there was a problem with it" is far more common for invoices sent two weeks late than same-day.

The fix: Invoice the same day the job is done - ideally before you leave site. Mobile invoicing apps like Tradify, Xero, or MYOB let you do this from your phone in 5 minutes. If you're managing larger projects, set a milestone billing schedule in writing before you start: deposit at signing, progress at agreed milestone, final at practical completion.

Mistake 2: Vague payment terms

"Payment on receipt" is not a payment term. It means nothing. Receipt of what? The invoice? The goods? "Net 30" is marginally better but still leaves the due date unspecified - 30 days from invoice date? From delivery? From the end of the month?

Vague terms create ambiguity, and ambiguity is a gift to slow payers. They exploit it, consciously or not, by treating "net 30" as an approximate guide rather than a deadline.

The fix: Use a specific calendar date. "Payment due by 15 June 2025" is unambiguous. It's harder to ignore, it gives you a clear trigger for follow-up, and it removes the mental negotiation a vague term invites.

For new clients, standard NZ residential terms are 7-14 days from invoice date. For ongoing commercial clients, 20 days is reasonable. For government or large contractor work, 20-30 days is typical.

Put your payment terms on your quote, on your invoice, and - ideally - in a brief one-line sentence in your standard email when you send the invoice: "Payment due by [date] as per terms."

Mistake 3: No follow-up system

Sending an invoice and waiting for the money to arrive is not a system - it's hope. Invoices don't pay themselves. Without a consistent follow-up schedule, you're dependent on every client having perfect payment habits, and some of them don't.

The research is consistent: a prompt reminder before the due date significantly increases the likelihood of on-time payment. Most late payments happen because someone genuinely forgot, or the invoice got buried in an inbox, or it's sitting with the wrong person in the accounts department.

The fix: Build a fixed follow-up schedule and stick to it:

3 days before due: Friendly reminder - "Just a reminder that invoice [number] for $[amount] is due on [date]. Bank details are on the invoice."
Due date + 1: Written reminder - "Invoice [number] was due yesterday. Please arrange payment today."
Due date + 5: Phone call - calm, direct, asking for a specific payment date
Due date + 10: Second written follow-up
Due date + 14: Formal written demand with a final deadline
Due date + 21: Escalate - professional follow-up service, Disputes Tribunal, or both

Most payments happen at the reminder stage. The clients who need you to hit day 14 before they pay are a small minority - but without the system, they cost you disproportionately.

Mistake 4: Accepting verbal payment promises

"I'll sort it Monday" is not a payment plan. "I'll pay in two instalments" is not an agreement. Verbal promises are easy to make and easy to backtrack on - especially when Monday comes and goes.

This mistake costs NZ tradies money in two ways:

The promise doesn't materialise, and you've lost follow-up momentum
You've accepted a modified arrangement without a written record, which makes formal recovery harder

The fix: Anytime a client asks for more time or a payment arrangement, confirm it in writing immediately. A simple reply-to-email is sufficient: "Thanks for the call. To confirm: you'll pay $[amount] by [date] and the remaining $[amount] by [date]." All you need is a date-stamped written record.

If they don't reply to confirm, send a follow-up: "I haven't heard back - is the arrangement above correct?"

With a written record, any failure to honour the arrangement becomes straightforward grounds for escalation. Without it, you're back to a he-said-she-said situation.

Mistake 5: Waiting too long before escalating

The data on invoice recovery is clear: the older a debt, the harder it is to collect.

Invoices chased within 30 days of the due date have a significantly higher recovery rate than those left for 60, 90, or 120 days. By the time you've sent a polite email three weeks after the due date, a less-scrupulous debtor has had time to deplete their account, start disputing the work retroactively, or simply stop responding altogether.

Why tradies wait too long:

It feels awkward to chase money
They hope the client will pay eventually
They don't want to damage the relationship
They're too busy on the tools to deal with it

All of these are understandable, and all of them are costing you money. A professional, calm follow-up on day 1 of being overdue is not aggressive - it's normal business practice. Waiting 30+ days before you chase is not being polite; it's training clients that your due dates are suggestions.

The fix: Set a non-negotiable escalation trigger. If a payment is 14 days overdue and two follow-ups have been ignored, escalate - without exception. Options include:

The Disputes Tribunal (for amounts up to $60,000)
A professional invoice follow-up service
A formal letter of demand from a solicitor

For a step-by-step guide on the escalation process, see our guide to what to do when a client refuses to pay.

Bonus mistake: Not using deposits

A deposit isn't a lack of trust - it's standard practice in most trade industries and expected by most professional clients. Not requiring deposits is a cashflow mistake as much as an invoicing one.

For any job over $500, a deposit of 30-50% upfront:

Covers your materials cost before you're out of pocket
Reduces the total amount at risk if payment becomes a problem
Confirms the client is serious

Clients who refuse a reasonable deposit are often the ones who'll give you trouble later. The deposit conversation is a useful filter.

Bonus mistake: Incomplete or missing GST information

Under the Goods and Services Tax Act 1985, a tax invoice for amounts over $50 must include your GST number. If you're unsure how much GST to charge, use our free GST calculator to work it out in seconds. An invoice without your GST number is not technically a valid tax invoice - which gives a GST-registered client grounds to query it before paying.

For invoices over $1,000, you also need the buyer's name and address, and GST shown separately (or a statement that it's included).

This is a 30-second fix - add your GST number to your invoice template if it isn't already there.

The pattern behind all of these mistakes

Look at the five mistakes above and you'll notice a pattern: they're all process failures, not relationship failures. You're not getting paid slowly because your clients are bad people. You're getting paid slowly because:

You're not triggering the payment process as early as you should
You're not making the payment deadline unambiguous
You're not following up consistently
You're not documenting agreements
You're not escalating when you should

Fix the process and you fix the cashflow. No difficult conversations required - just consistency.

FAQ

How do I invoice for variations without causing a dispute? Get variation approval in writing before you do the extra work - even a text or email saying "confirmed, go ahead" is sufficient. Send the variation invoice as a separate line item on the next invoice, referencing the approval. A surprise variation on the final invoice is the most common trigger for invoice disputes.

What's the best invoicing software for a sole trader NZ tradie? Hnry is purpose-built for NZ sole traders and handles GST automatically. Tradify is excellent for tradies who want job management and invoicing in one tool. Xero is the dominant NZ accounting platform and integrates with almost everything. All three have good mobile apps.

Can I charge interest on overdue invoices? Yes - but only if it was agreed in your payment terms upfront. You cannot add interest retrospectively. A common rate is 2-3% per month on overdue amounts. Include your late payment terms on every quote and invoice if you intend to use them.

Do I need a written contract or is a verbal agreement enough? A verbal agreement is legally enforceable in NZ, but it's much harder to prove in a dispute. For any job over $500, get something in writing - even a brief email confirming the scope and price. The threshold for a written quote is lower than most tradies think: any job you'd be upset about not getting paid for.

What do I do if a client claims the work wasn't done properly to avoid paying? Get the specific complaint in writing immediately. Do not agree verbally to reduce the invoice. Respond in writing addressing each point, with photos or other evidence if available. If the complaint is genuine, offer to remedy the specific issue - not to reduce the overall invoice. Most quality disputes that are raised only after you chase payment are not genuine quality disputes.

Update log

16 June 2026 - Updated the Disputes Tribunal jurisdiction limit to $60,000 (was $30,000). Why: the Tribunal's financial jurisdiction increased to $60,000, effective 24 January 2026. Source: Ministry of Justice.
20 April 2025 - Guide first published.

Last reviewed: 16 June 2026.