Winkel Factuur Insights
As an entrepreneur, you want to get paid for your work. A correct invoice is the foundation for this. But how do you create an invoice that meets all regulations? In this complete guide, we explain step-by-step how to create a professional invoice, what details are mandatory, and how to automate this process.
To make an invoice, include your business details, a unique invoice number, date, customer info, item descriptions with prices, VAT amounts, and the total due.
New business owners are unsure what information an invoice must contain and how to format it correctly. This step-by-step guide walks you through every required field and best practice for creating a legally valid invoice.
An invoice is an official document requesting payment for goods or services provided. It is not only a payment request to your customer but also an essential part of your administration for tax authorities.
A correct invoice ensures:
• Faster payment: Clear invoices get paid faster.
• VAT deduction: Your business customers need a valid invoice to reclaim VAT.
• Proof of transaction: It is the legal proof of the transaction and the payment obligation.
• Professional image: A neat invoice builds trust.
Do you want to make an invoice yourself? Follow these steps to ensure you don't forget anything.
Step 1: Gather your business details
Ensure your own details are complete: company name, address, Chamber of Commerce number, VAT number, and IBAN.
Step 2: Request your customer's details
For business invoices, you need the full company name and address of your customer. For sales to private individuals, this is less strict but recommended.
Step 3: Determine the invoice number
Use a unique, sequential number. For example: 2025-001, 2025-002, etc. You are not allowed to leave gaps in the numbering.
Step 4: Describe the delivery
Be clear about what you have delivered. 'Services January' is often too vague. Specify hours, products, or project parts.
Step 5: Calculate the amounts
State the amount excluding VAT, the VAT percentage (21%, 9%, or 0%), the VAT amount, and the total amount including VAT.
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Start free trial →Tax authorities have strict requirements for invoices. If your invoice does not meet these requirements, your customer cannot deduct the VAT, and you may receive a fine. Ensure the following details are always on your invoice:
• Your details: Company name, address, CoC number, VAT number.
• Customer details: Name and address. For B2B (business) also the customer's VAT number (especially for export within the EU).
• Invoice number: Unique and sequential.
• Invoice date: The date you send the invoice.
• Delivery date: The date the goods or services were delivered.
• Description: Clear description of the goods or services.
• Quantity and price: Quantity and price per unit (excl. VAT).
• VAT rate: The applied rate (21%, 9%, 0%, or exempt).
• VAT amount: The amount of VAT in euros.
• Total amount: The amount to be paid (incl. VAT).
You can create invoices in different ways. What works best for you depends on the size of your business and the number of invoices.
1. Invoice in Word or Excel
Many starters begin with this. You create a template and fill it in manually each time.
Advantage: Free and flexible.
Disadvantage: Error-prone (wrong calculation, duplicate numbers), time-consuming, and looks less professional.
2. Online invoicing software
Special software for bookkeeping and invoicing.
Advantage: Automatic numbering, payment links, professional layout.
Disadvantage: Monthly costs.
3. Automated invoicing (for webshops)
Do you have a webshop (Shopify, WooCommerce, bol.com)? Then manual invoicing is not an option. Use a tool like Winkel Factuur to automatically generate and send invoices for every order.
Advantage: No manual work, always error-free, direct integration with your webshop.
Sometimes you need to create an invoice with 'Reverse Charge VAT'. This means you do not charge VAT, but the customer must declare the VAT in their own country. This occurs with:
• Subcontracting in construction and cleaning.
• Delivery of mobile phones, chips, and laptops (above a certain amount).
• Export to entrepreneurs in other EU countries (Intra-Community supply).
On the invoice, you do not state a VAT amount, but the text 'VAT Reverse Charge'. Always mention the customer's VAT number.
Avoid these common mistakes:
• Wrong VAT rate: Check if you should charge 21% or 9%.
• Non-sequential numbers: Gaps in your numbering raise questions with tax authorities.
• Late invoicing: You must invoice by the 15th of the month following delivery.
• Missing details: Don't forget your CoC number or VAT number.
• Not keeping invoices: You have a retention obligation of 7 years.
Selling online? Then creating invoices manually is a waste of your time. Winkel Factuur connects directly to your webshop (Shopify, WooCommerce, bol.com, Amazon) and automatically creates a perfect invoice for every order.
• Save time: Never retype data again.
• Prevent errors: Always the correct VAT rate and invoice number.
• Professional: Invoices in your own branding.
• Multilingual: Automatic invoices in your customer's language.
Try it now for free and discover the convenience of automated invoicing.
Every invoice must include your company name, address, Chamber of Commerce number, and VAT number. You also need the customer's details, a unique sequential invoice number, invoice date, delivery date, a clear description of goods or services, quantity, price per unit, VAT rate and amount, and the total including VAT.
Use unique, sequential numbers without gaps. A common format is year-number, such as 2025-001, 2025-002, and so on. You are not allowed to leave gaps in the numbering, as this raises questions with tax authorities.
Reverse charge applies when selling to businesses in other EU countries (intra-community supply), subcontracting in construction and cleaning, and delivering certain goods like mobile phones and laptops above specified amounts. You state 'VAT Reverse Charge' on the invoice instead of a VAT amount.
You must send the invoice by the 15th of the month following delivery. Invoicing too late risks a fine from tax authorities and may also cause problems with VAT reporting, as you must declare turnover in the period when you should have invoiced.
For occasional invoices, templates can work, but they are error-prone and time-consuming. For webshops with regular orders, automated invoicing software is strongly recommended. It handles numbering, VAT calculation, and delivery automatically.
Connect your webshop to Winkel Factuur and automate your entire invoicing process. Error-free, fast, and professional. Start for free today.
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