IT Consulting Invoice Template - New Zealand

You must register for GST if your annual turnover exceeds NZD $60,000. Once registered, you charge 15% GST on all IT consulting services and remit it to the IRD. If you're below the threshold, you're not required to register, meaning you cannot charge GST but also don't collect it from clients. On invoices, clearly display your GST registration number if registered, and itemize the GST amount separately from your subtotal. This applies regardless of whether you work as a sole trader or limited company.

New Zealand law requires your invoices to include: your business name and GST registration number (if registered), invoice number and date, clear description of IT services provided, total amount payable, and your contact details. Your client's name and address should also be recorded. Include payment terms and due date to set clear expectations. Service descriptions should be specific—"Network Assessment" is better than "IT Work." These details protect you legally and help clients process invoices quickly for payment approval.

Each model suits different situations. Hourly rates (typically NZD $85–150 per hour for IT consulting) work well for time-intensive work like system monitoring or troubleshooting where scope varies. Fixed-price invoicing suits well-defined projects like network setup or security audits where you can estimate hours accurately. Retainers are ideal for ongoing support relationships, providing clients predictable costs and you reliable revenue. Many consultants combine models—retainers for maintenance plus fixed rates for specific projects. Choose based on client needs, project predictability, and your cash flow preferences.

Most New Zealand businesses expect Net 15 (payment within 15 days) or Net 30 payment terms on consulting invoices. Net 30 is standard for larger projects or corporate clients. For smaller jobs under NZD $500, some consultants request Net 7 or even payment on invoice. Always specify your payment terms clearly on the invoice—ambiguity causes disputes and delays cash flow. Consider requesting 50% upfront for projects exceeding NZD $5,000 to manage your working capital. Building good payment practices early protects your business and sets professional expectations.

Itemizing each IT service separately is generally better, especially for consulting. It shows clients exactly what they're paying for—"Network Infrastructure Assessment" is clearer than bundling it into "IT Services." Separate line items help clients understand the scope and justify costs internally to their stakeholders. This transparency reduces invoice disputes and makes retainer breakdowns easier. However, for simple invoices with one or two services, grouping is acceptable. Match your approach to client expectations: corporate clients usually prefer detailed itemization, while smaller businesses may prefer simplicity.

When invoicing remote IT consulting, always describe the work performed and the deliverables clearly. Instead of "Cybersecurity Consultation," specify "Cybersecurity Audit – Review of 12 workstations, firewall configuration, and risk report." If charged hourly, note the hours worked or estimated hours. Reference any agreed scope document, statement of work, or project brief from your initial client conversation. Remote work often lacks tangible physical output, so detailed descriptions become crucial for client understanding and payment justification. Include dates of service and list specific systems, software, or processes you addressed.

Yes, retainer invoices are standard in IT consulting and perfectly acceptable in New Zealand. A retainer invoice should specify the retainer period (e.g., "Monthly IT Support – July 2025"), the retainer fee amount, and what services are included in that fee. State clearly if the retainer covers unlimited support or a set number of hours monthly. If clients exceed retainer hours, clearly communicate overage rates on future invoices. Recurring monthly invoices build predictable revenue and simplify your invoicing process. Use invoice templates that support automatic date and invoice number sequencing for retainer billing.

Common mistakes include invoicing late, which delays cash flow significantly. Providing vague descriptions like "IT Work" instead of specific tasks creates payment disputes. Forgetting GST registration numbers damages tax compliance records. Inconsistent invoice numbering confuses your accounting. Not specifying payment terms leaves clients uncertain about deadlines. Some consultants fail to detail retainer hours used, creating client confusion. Many don't follow up on overdue invoices within 7–10 days, allowing debts to age unnecessarily. Not including a payment contact method frustrates clients. Addressing these patterns improves payment speed and professionalism.