Service descriptions on invoices: How freelancers in Switzerland avoid common mistakes

An invoice can be formally correct — IBAN matches, VAT rate is right, QR-bill is included — and still cause problems. The most common reason: the service description is too vague, too technical, or simply incomplete. Accountants at the client's end can't categorise it, the Swiss tax office won't accept it during an audit, and in a dispute, it's nearly impossible to prove what was actually delivered. This article shows exactly what matters when describing services — and which formulations Swiss freelancers should avoid.

Why the service description is so critical

In Switzerland, an invoice serves two purposes at once: it's the basis for the client's VAT recovery and proof of work performed for the tax authorities. Both functions depend entirely on the quality of the service description. If an accountant receives an invoice with the text "Services May 2026", they can't easily assign it to a cost centre. That leads to follow-up questions, payment delays — and in the worst case, the client's VAT recovery gets rejected.

For freelancers, this is doubly risky: failing to describe your work clearly signals unprofessionalism and endangers the business relationship. Yet the solution is usually straightforward.

The three most common description mistakes

1. Too generic: "consulting", "support", "development"

Such umbrella terms tell you nothing about the subject matter, scope, or result. Better: name the context and specific outcome.

Instead of: "Consulting March 2026"
Better: "Strategic consulting for the launch of a new product segment, 8 h @ CHF 180.–, as per quote dated 12.02.2026"

2. Too technical without explanation

IT freelancers, developers, or engineers often use internal project names or ticket numbers that only exist in their own system.

Instead of: "Implementation Sprint #14, Ticket 4521–4533"
Better: "Development of login module (user authentication) according to specification v2.3, Sprint 14, 22 h @ CHF 145.–"

The ticket number can appear as a supplementary detail — it's not enough as the primary description.

3. Missing time reference for flat-rate fees

If you invoice monthly retainers — for example for ongoing content management or SEO support — you must state the service period. Without this, the invoice is incomplete, and correct accounting at the client end becomes difficult.

Instead of: "Monthly website support, CHF 1'200.–"
Better: "Ongoing website editing and SEO maintenance, service period 01.08.–31.08.2026, flat rate as per contract dated 15.01.2026"

What a complete service description contains

A good description answers four key questions:

Question	Example
What was delivered?	Concept and copy for 2025 annual report
How much of it?	18 h or 1 flat fee, page count, quantity
When was it delivered?	Period or delivery date
What is it based on?	Reference to quote, contract, or purchase order

Not every invoice needs to spell out all four points explicitly — for a clearly defined one-off job, a reference to the quote may suffice. What matters is that the invoice is understandable to a third party: an accountant, auditor, or tax official.

VAT obligation and service description: a direct connection

If you're subject to VAT, you should know: the tax office can require during an audit that the VAT you've charged matches the actual rate of the service provided. A vague description complicates this verification. It's especially relevant when freelancers invoice both standard-rate services (8.1%) and reduced-rate services (e.g. 2.6% for printed products) on the same invoice — it must be immediately clear which line item falls under which rate.

If you'd like to refresh your knowledge of VAT fundamentals in Switzerland, our article on Swiss VAT basics 2026 — rates, duties and special rules offers a comprehensive overview.

Practical wording templates

A proven pattern for time-based invoicing:

[Activity], [project/client context], [period or date], [number of hours] h @ CHF [rate], as per [quote/order no. X]

For flat-rate fees:

[Service description], service period [from]–[to], flat rate as per [contract/agreement dated]

For one-off deliverables:

[Service], delivered on [date], as per quote no. [X] dated [date]

These templates can easily be saved as standard formats and adapted for each job. If you invoice regularly for similar work, you'll save considerable time.

Multiple services on a single invoice

When freelancers bundle different activities — for example concept, copy, and coordination — it's best to list these as separate line items, each with its own description, hours, and rate. This makes cost allocation easier for the client and ensures clarity during VAT audits. A compact practical guide to the entire invoicing process can be found in our article Freelance invoicing in Switzerland — practical guide.

For creating structured invoices digitally with QR-codes and multiple line items, the SnapBill app lets you enter and label each position individually.

What if an invoice has already been sent?

If you've already sent an invoice with an incomplete description and the client asks for clarification: a brief written supplement via email referencing the invoice number and clarifying the service is usually sufficient. This correspondence will be archived as supporting documentation. A formal invoice correction is only necessary if the amount, VAT rate, or sender/recipient details change.

At a glance

• Too vague, too technical, missing time reference — these are the three main errors in service descriptions.
• A good description answers: What? How much? When? What is it based on?
• References to quotes, contract numbers, or order dates aren't an end in themselves — they make your invoice usable in case of dispute.
• When mixing VAT rates on a single invoice, each line must be assigned to the correct rate.
• Standard templates with proven wording save time and reduce errors permanently.
• A follow-up clarification via email is possible — as long as the amount and tax rate remain unchanged.