Invoice Required Fields for Swiss Freelancers: 7 Mistakes to Avoid

As a freelancer in Switzerland, your invoice is more than just a payment trigger — it's also a tax document. If a required field is missing, your client's accounting department will refuse the input tax deduction, payment gets delayed, or you'll receive correspondence from the Federal Tax Administration (ESTV). The good news: the most common mistakes follow a pattern and can be completely avoided with a little system.

Why required fields matter on freelancer invoices

An invoice that serves as a VAT receipt must meet statutory minimum requirements — this is governed by Article 26 of the VAT Act. Your client can only deduct input tax if your invoice is complete. If their accounting department flags an error, the ball is back in your court: you must issue a corrected invoice, which costs time and sometimes trust.

For freelancers without VAT registration, stricter requirements don't apply, but complete information still protects you from misunderstandings and later disputes.

The 7 most common mistakes — and how to avoid them

1. Missing or incorrect VAT number

Once you're VAT-registered (from CHF 100,000 annual turnover or voluntary registration), your UID with the addition "VAT" must appear on every invoice: e.g. CHE-123.456.789 VAT. If only the UID without this addition appears, the tax proof is missing. Also check that your UID is listed correctly in the federal UID register.

2. No applicable VAT rate stated

Many freelancers simply write "incl. VAT" on the invoice without specifying the tax rate. That's not enough. Since 1 January 2024, the following rates apply in Switzerland:

Category	Rate
Standard rate (most services)	8.1%
Special rate accommodation	3.8%
Reduced rate (food, books, etc.)	2.6%

As a freelancer in IT, communications or consulting, the standard rate of 8.1% almost always applies. Show net amount, VAT amount, and gross amount separately. For a compact overview of all current rates and special rules, see the article on Swiss VAT basics 2026 — rates, duties and special rules.

3. Invoice number missing or not unique

The invoice number must be sequential and unique. "Invoice 1" on 1 January and again "Invoice 1" the next year is fine as long as you don't create a duplicate in the same period. A schema like 2026-001, 2026-002 etc. has proven effective. If the number is missing entirely, the document is not a valid receipt.

4. Service description too vague

"Consulting June 2026" tells neither your client nor a reviewer anything substantive. Describe the service delivered so that an outsider understands what was provided: "Conception and writing website copy for product XY, 14–28 June 2026, 18 hours at CHF 130". For time-based services, a time record as an attachment or invoice detail is also recommended — what exactly belongs on the invoice is explained in the guide to time records on invoices.

5. Incorrect or missing bank details (IBAN vs. QR-IBAN)

Since the old payment slip was completely phased out, invoices with a payment section must use the QR-IBAN, not the classic IBAN. Both start with "CH" but differ in the check digit. If you use a classic IBAN without a QR payment section, that's not an error — as long as you don't include a QR code. But if you combine a QR code with a classic IBAN, your client's bank will reject the payment.

6. Service date missing

The invoice date and the date the service was performed are two different things. VAT law requires that the invoice shows when the service was provided. If you worked over several weeks, a time period is sufficient: "Service period: 1–30 May 2026".

7. Recipient details incomplete

Business clients need their full company name and address on the invoice to claim input tax deduction. "Sample AG" is sufficient — "Sample" without legal form or without an address is not. Ask new clients early for the correct invoice recipient details (company name, department, postal code, city).

Checklist: Review before sending

• Complete sender details (name, address, company name if applicable)
• Complete recipient details
• Unique invoice number
• Invoice date
• Service period or service date
• Detailed service description
• Net amount, VAT rate, VAT amount, gross amount (if VAT-registered)
• UID with "VAT" addition (if VAT-registered)
• Correct bank details (IBAN or QR-IBAN matching the payment section)
• Payment terms

The Swiss invoice template with all required fields brings together all mandatory fields at a glance and in printable form — a useful starting point before you build your own template.

Non-VAT-registered freelancers: What applies to you?

If you stay below the CHF 100,000 turnover threshold and are not voluntarily registered, you don't have to show VAT. But that doesn't mean anything goes: never write "excl. VAT" or "0% VAT" on an invoice without registration — this implies VAT registration that doesn't exist. Correct is either: no VAT mention, or the sentence "Not VAT-registered in accordance with Article 10 para. 2 VAT Act".

Create invoices directly, without errors

If you issue invoices frequently, a tool that automatically checks required fields and generates QR payment sections correctly is worthwhile. The SnapBill app guides you through all required fields and creates QR invoices compliant with SIX standards — without you having to manually look up every requirement.

At a glance

The most common errors on Swiss freelancer invoices are: missing or incorrect VAT number, incomplete tax declaration, vague service descriptions, and incorrect bank details. With a short checklist before each send and clean templates, these errors can be systematically eliminated. Non-VAT-registered freelancers don't need to show tax, but shouldn't send false signals either. Complete invoices protect your client, secure your payment — and save you correspondence with the ESTV.