Money Matters

How to write an invoice and what to include

Learn how to create invoices to get paid on time with our invoice cheat sheet. Discover what to include, invoice types, common payment terms, and tips to avoid overdue invoices.

Published September 3, 20261 min read Share

An invoice is a document that asks a customer to pay for goods or services.

A clear invoice identifies the supplier and customer, explains what was supplied, states the amount due, and tells the customer when and how to pay.

Using a consistent invoice format can make each bill easier to understand, track, and process.

If your business is registered for value-added tax (VAT) in South Africa, you may also need to issue a tax invoice that meets South African Revenue Service (SARS) requirements.

Key takeaways

• Include a unique invoice number, invoice date, customer details, a clear description of what you supplied, the total due, payment terms, and payment instructions.
• If you are VAT-registered in South Africa, a standard invoice may not be enough. SARS tax invoice requirements can apply to taxable supplies.
• Use the invoice type that matches the transaction, such as a Pro Forma, interim, final, recurring, credit, or debit invoice.
• Agree payment terms in advance, show a clear due date, and follow up promptly when an invoice becomes overdue.

Here’s what we’ll cover:

What is an invoice?

An invoice is a document a business sends to a customer to describe the goods or services supplied and request payment.

It normally shows the total amount owed, the invoice date, the customer and supplier details, and the payment due date.

A standard invoice must show:

What to include on a standard invoice

A standard invoice should give your customer enough information to understand the charge, approve it, and make payment.

Include the following details:

• The word ‘invoice’
• Your company name and contact details
• Your customer’s name and address
• Invoice date
• Unique invoice number
• Purchase order number, if applicable
• Payment due date
• Description of the goods or services supplied
• Quantity and unit price, where relevant
• Total amount due
• Accepted payment methods and payment instructions
• Payment terms
• Date the goods or services were supplied, if different from the invoice date
• Any relevant notes

1. The word “invoice”

Place the word “Invoice” near the top of the document so the customer can distinguish it from a receipt, order, or quote.

2. Your company name and contact details

Include your company name, business address, phone number, and email address.

This gives the customer a clear way to contact you about the invoice.

3. Your customer’s name and contact details

Address the invoice to the customer and include the correct billing contact and address.

4. Invoice date

Use the date the invoice was created.

Payment terms are generally calculated from this date, so it helps you and your customer confirm when payment is due.

5. Invoice number

Give every invoice a unique number.

A sequential numbering system makes invoices easier to track and reduces the risk of duplicates.

An invoice number can include letters and numbers.

6. Purchase order number, if applicable

If the customer gives you a purchase order number, add it to the invoice.

This helps the customer match the invoice to an approved purchase and may speed up processing.

7. Invoice due date

State the latest date the customer should pay.

Base the date on the payment terms you agreed.

For example, if an invoice dated 1 July has 30-day payment terms, the due date is 31 July.

8. Description, quantity, and unit price

Describe each item or service clearly.

Where relevant, show the quantity and price per unit so the customer can check that the invoice matches what was ordered.

9. Total amount due

Show the total amount the customer must pay for all goods or services listed on the invoice.

10. Accepted payment methods and instructions

Tell the customer how to pay.

Options may include cash, cheque, credit or debit card, electronic funds transfer (EFT), an instant payment option such as PayShap, PayPal, or mobile payment apps such as SnapScan and Zapper.

11. Payment terms

State the agreed payment period and any applicable late payment policy.

Even where a late payment policy is not required, including it can remind the customer to pay on time.

12. Date goods or services were supplied

If the supply date differs from the invoice date, show it with the relevant line item.

This helps the customer identify what the invoice covers.

13. Notes

Use the notes area for useful additional information, such as a thank-you message, terms and conditions of sale, or return and refund procedures.

Some online accounting software can add payment options to an invoice.

Explore accounting software from Sage or integrated payment solutions where these are relevant to your business.

Do you need to issue a SARS tax invoice?

If your business is registered for VAT, a standard invoice isn’t always enough.

Under South Africa’s VAT Act, VAT-registered vendors must issue a tax invoice (also called a VAT invoice) for taxable supplies, so the customer can claim input VAT and SARS has a valid record of the transaction.

• Supplies of R50 or less: a tax invoice generally isn’t required.
• Supplies between R50 and R5,000: an abridged tax invoice is allowed, and doesn’t need the recipient’s details.
• Supplies over R5,000: a full tax invoice is required, showing the words ‘Tax Invoice’, ‘VAT Invoice’ or ‘Invoice’; the supplier’s name, address and VAT registration number; the recipient’s name, address and VAT number (where registered); a serial invoice number and date; a description and quantity of the goods or services; and the value, VAT amount, and VAT-inclusive total.

A tax invoice must generally be issued within 21 days of the supply, and VAT records should be kept for five years.

This is general guidance only.

Confirm the current thresholds and requirements with SARS or your tax practitioner before relying on it.

Different types of invoices

Pro Forma invoice

A Pro Forma invoice is sent before goods are delivered or services are provided.

It gives the customer an estimate of the expected cost.

It is often marked “Pro Forma invoice” to show that it is preliminary and does not request payment.

Common uses include international shipments for customs clearance, quotes, custom orders, and insurance cover for valuable goods in transit.

Interim or progress invoice

For a long-term project, you and the customer may agree to issue invoices when specific milestones are reached.

Progress invoicing supports cash flow during the project instead of leaving the full amount until completion.

Final invoice

A final invoice is sent when a transaction or project is complete.

Where interim invoices have been used, it summarises the earlier invoices and shows any balance still due.

Credit memo

A credit memo reduces the amount originally billed.

You may issue one after an overcharge, damaged or expired goods, or a difference between what the customer ordered and what was supplied.

Debit memo

A debit memo increases the amount originally billed.

Reasons can include interest or late fees, freight or shipping charges left off the original invoice, or agreed variable-cost adjustments.

Recurring invoice

A recurring invoice bills the same customer at regular intervals for services such as:

• subscriptions,
• retainers,
• membership fees,
• software licences,
• or accounting services.

Past due invoice

A past due invoice can be sent after the original payment date has passed.

Mark it clearly as “Past Due Invoice”.

An outstanding invoice is unpaid but not yet overdue.

A past due invoice is unpaid after its due date.

Electronic invoice

An electronic invoice is sent digitally rather than by post.

It reaches the customer quickly and can help remove postal delays from the collection process.

Cloud-based invoicing software can help create recurring invoices, send them to customers, and issue overdue reminders.

What are common invoice payment terms?

Payment terms explain when the customer must pay.

Use plain language, agree the terms before starting work where possible, and always show the exact due date on the invoice.

Due upon receipt

The customer should pay when the invoice is received, typically by the next business day.

This term is often used for one-off services, new customers without an established payment history, custom orders, or higher-risk transactions.

Net payment terms

A Net term means payment is due a set number of days after the invoice date.

Net 15 gives the customer 15 days to pay, Net 30 gives 30 days, Net 45 gives 45 days, and Net 60 gives 60 days.

Longer terms can delay cash coming into your business, so consider the effect on day-to-day cash flow.

2/10, Net 30

The customer receives a 2% discount if they pay within ten days.

Otherwise, the full amount is due 30 days after the invoice date.

Similar terms include 1/15, Net 30 and 1/10, Net 30.

Cash on delivery

Cash on delivery (COD) means the customer pays when the goods are delivered, rather than before shipment.

Which invoice payment methods can you offer?

The right payment methods depend on your customers, industry, costs, and cash flow needs.

Give clear payment instructions and only list methods your business accepts.

Credit or debit card

Card payments usually require a merchant account and either a card reader for in-person payments or a payment gateway for online payments.

Costs vary by provider, transaction volume, and card type.

Cheque

Cheques can take longer to receive and clear than electronic payments.

They can also be lost in the post or returned because of insufficient funds.

Electronic funds transfer

Electronic funds transfer (EFT) is a direct bank-to-bank payment and is commonly used by South African businesses.

Processing time and cost depend on the banks involved.

Wire transfer

Wire transfers are often used for international payments.

Processing times and charges depend on the sending and receiving banks.

PayPal

PayPal allows customers to send money electronically and can support payments from customers in other countries.

Mobile payment apps

Apps such as SnapScan and Zapper can let a customer pay by scanning a QR code with a smartphone.

Direct debit

A direct debit can support subscriptions or other regular payments.

You need the customer’s authorisation before taking payment from their bank account.

How should you send an invoice?

Send an invoice as soon as possible after the goods are supplied or the work is completed, unless your contract sets a different billing schedule.

1. Confirm that the customer name, billing contact, purchase order number, line items, totals, and due date are correct.
2. Save the final invoice as a PDF so the layout is less likely to be changed accidentally.
3. Use a clear email subject line that includes your company name, the invoice number, and the period or work covered.
4. Keep the email short and state the amount due, due date, and payment instructions.
5. Send the invoice to the person responsible for payments and keep their phone number and email address for follow-up.

When selling goods, you may invoice when they are shipped if you did not take payment in advance.

For services, you may invoice at the end of a project or at an agreed month-end billing point.

If you are VAT-registered, make sure your VAT number and company registration details are included on the invoice.

Your customer will need these details for their own tax and accounting records.

How can you improve your chances of being paid on time?

• Agree clear terms and conditions before work starts.
• Confirm the payment terms and exact due date.
• Ask for a purchase order number where the customer uses one.
• Consider asking a new customer to pay the first invoice in advance.
• For large or long-term projects, agree milestone payments.
• Offer a payment method that is practical for the customer and suitable for your business.
• Monitor unpaid invoices and follow up promptly when the due date passes.

For more strategies, see our guide on ways to get paid on time.

What should you do when an invoice is overdue?

1. Check your records to make sure the payment has not already been received or allocated to the wrong customer account.
2. Send a polite reminder and attach the original invoice again.
3. If payment still does not arrive, send a formal written reminder that states the overdue amount and any applicable late fees.
4. Consider a payment arrangement if the customer is experiencing financial difficulty and this is appropriate for your business.
5. If the invoice remains unpaid, send a final notice that explains the next steps, which may include using a collection agency.
6. Keep each follow-up factual and professional. Record when reminders were sent and any response from the customer.

Managing overdue invoices is a key part of accounts receivable.

Understanding the accounts payable process from your customer’s perspective can also help you structure invoices for faster processing.

Invoice checklist

• Invoice is clearly labelled and has a unique number.
• Supplier and customer details are correct.
• Goods or services, quantities, prices, and totals are clear.
• Invoice date, supply date, payment terms, and due date are consistent.
• Payment instructions are complete.
• Purchase order and VAT details are included where applicable.
• Final invoice has been saved as a PDF and sent to the correct billing contact.

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Ready-made invoice templates can help a small business get started.

Businesses that issue invoices regularly may also benefit from software that creates invoices and schedules reminders.

Explore financial management software and automated billing software from Sage.

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Frequently asked questions on writing invoices in South Africa

What is the difference between an invoice and a tax invoice?

A standard invoice is a request for payment.

A tax invoice, also called a VAT invoice, is issued by a VAT-registered business and must meet applicable SARS requirements so the customer can claim input VAT.

Do I need to charge VAT on my invoices?

Only if your business is registered for VAT with SARS.

If you are not VAT-registered, you should not add VAT to your invoices.

What must a South African tax invoice include?

For supplies over R5,000:

• a full tax invoice must include the words ‘Tax Invoice’,
• your business’s name,
• address and VAT number,
• the customer’s details,
• an invoice number and date,
• a description of goods or services, and the value, VAT amount, and total.

Always confirm current requirements with SARS or your tax practitioner.

How soon after supplying goods or services should I send an invoice?

Send it as soon as possible, or at the billing point agreed in your contract.

Tax invoices generally need to be issued within 21 days of the supply.

What is the difference between a Pro Forma invoice and a tax invoice?

A Pro Forma invoice gives a customer an estimated cost before a sale is finalised and is not a request for payment.

A tax invoice is issued after a taxable supply and must meet applicable SARS requirements.

What are common invoice payment terms in South Africa?

Common options include:

• payment due upon receipt,
• Net terms such as Net 30,
• early-payment discount terms such as 2/10,
• Net 30,
• and cash on delivery.

The best term depends on what you and the customer agree.

Learn more about how to negotiate payment terms with your customers.

How long should I keep copies of my invoices?

SARS generally requires VAT records, including tax invoices, to be kept for five years.

Confirm current retention requirements with SARS or your accountant.

If you hate bookkeeping, there are ways to make record-keeping less painful.

What should I do if a customer does not pay on time?

• Check that payment has not already been received,
• send a friendly reminder,
• follow with a formal written reminder if needed,
• and consider a payment plan before escalating unpaid invoices to collections.

Editor’s note: This article was first published in February 2025 and has been updated for relevance.

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