A newsletter is quickly written. The harder question is who may receive it. Newsletter law Switzerland means competition law and data protection law at the same time: the UWG (Federal Act against Unfair Competition) governs when mass advertising by telecommunications is permitted, and the Federal Act on Data Protection (DSG) governs how email addresses are handled. This guide shows what the law says, what the authorities say about it, where the exception for customers ends and how to manage consent and unsubscribing cleanly in daily work.
The rule: Art. 3, para. 1 lit. o UWG
Under Art. 3, para. 1 lit. o UWG, it is unfair to send mass advertising by telecommunications without a direct connection to requested content, or to cause such mailings to be sent, and in doing so to fail to obtain customers’ prior consent, to give the correct sender or to point out a straightforward and free way of refusing. The law lists three duties joined by “or”: if one is missing, the advertising is unfair.
Three terms deserve a closer look:
- By telecommunications means in particular by email. The FDPIC, the Federal Data Protection and Information Commissioner, says so too.
- Mass advertising is not tied to a number. The Federal Office of Communications (OFCOM) states that no numerical limit is set; sending to several recipients can already be enough, and in each case the court decides. The page dates from 2019. Treat every bulk mailing as mass advertising.
- Requested content: the law excludes mailings that are directly connected with requested content. Someone who expressly asks for a piece of information and receives exactly that is therefore not affected. The regular newsletter is not the content someone requested with a price enquiry. To be safe, assume that it does not fall under this exclusion (interpretation, not statutory text).
The law speaks of “customers” and, in its wording, does not distinguish between private and business addresses. So plan for consent for company addresses too.
Consent: what it involves
The UWG says only “consent”. The FDPIC spells it out: email advertising is possible if people give their express consent before they are approached (opt-in). Consent is valid only if it is given voluntarily and after adequate information; the person must know that their address will be used for advertising. As an example, the FDPIC cites a box that the person ticks themselves. Accepting general terms and conditions is not enough. Consent may be withdrawn at any time.
The Federal Act on Data Protection adds in Art. 6, para. 6: where consent is required, it is valid only if it is given voluntarily for one or more specific processing operations after adequate information. In practice, this means that someone who signs up for “news” has not automatically consented to promotional emails. So record the purpose.
Two points are not in the law but are practice: first, you should be able to prove consent, with date, source and the text shown; in a dispute, you bear the consequences if you cannot produce anything. Second, a confirmation procedure by email (double opt-in) is not required by law, but it is good evidence.
The exception for customers
Art. 3, para. 1 lit. o UWG contains an exception. Anyone who obtains customers’ contact details in the sale of goods, works or services, and points out the option of refusing, does not act unfairly if they send those customers mass advertising for their own similar goods, works or services without their consent. All parts must be met together:
- The address comes from a sale to that person.
- You pointed out the possibility of refusing further advertising when collecting the address.
- The advertising concerns your own, similar offerings.
The FDPIC adds that the exception applies only if a sale has actually taken place or a service has actually been provided; an opened online account is not enough. Anyone with addresses from prospects, trade fair visitors or research cannot rely on this exception.
Sender and unsubscribing
The sender must be stated correctly. OFCOM requires that it must not be hidden or forged. Use your company name, an address at which you can be reached and a complete imprint in the footer.
Refusing must be straightforward and free of charge. The FDPIC describes a simple, free option, usually an unsubscribe link. OFCOM writes that anyone who clicks it must be removed from the list. What that means in practice (practice, not law): one click, no login, no reason required, effective immediately and for all newsletters from this sender. Many email programs also show their own unsubscribe button if the mailing is equipped for it; that is a technical standard, not a duty under Swiss law.
Data protection law: what else applies
Email addresses of natural persons are personal data, because they relate to an identified or identifiable person (Art. 5 lit. a DSG). An address such as firstname.lastname@company.ch counts; a general address such as info@company.ch generally does not, unless it can be assigned to a specific person, for example in a sole proprietorship (interpretation). The FDPIC states that personal data is processed when acquiring customers by email and that the DSG applies.
Three tasks follow:
- Inform. Under Art. 19 DSG, you provide at least your identity and contact details, the purpose of processing and, where applicable, the recipients of the data when you collect it. In practice, this goes into the privacy notice and the sign-up form.
- Stick to the purpose. Personal data may be collected only for a recognisable purpose and processed only in a way compatible with it (Art. 6, para. 3 DSG). If you measure opens, that belongs in the notice.
- Take objections seriously. An infringement of personality rights exists in particular where personal data is processed against the express wishes of the person concerned (Art. 30, para. 2 lit. b DSG). Someone who unsubscribes must receive no more advertising.
What happens in the event of breaches
Under civil law, a person who is threatened or harmed by unfair competition may sue under Art. 9 UWG, and so may customers (Art. 10, para. 1 UWG). Under criminal law, Art. 23, para. 1 UWG threatens intentional unfair competition under Art. 3, on complaint, with a custodial sentence of up to three years or a monetary penalty. If private persons intentionally fail to provide the information required by Art. 19 DSG, a fine of up to CHF 250’000 is threatened, on complaint (Art. 60, para. 1 lit. b DSG).
Telecommunications service providers also have duties: they combat unfair advertising under Art. 3, para. 1 lit. o, u and v UWG (Art. 45a, para. 1 FMG). If a provider learns that a customer is sending unfair advertising over its network, it must block the sending immediately and may disconnect the customer from the network (Art. 83, para. 4 FDV). According to the FDPIC, anyone who receives unauthorised email advertising can complain to SECO.
Practical example: Muster Gartenbau AG
Muster Gartenbau AG (fictitious) wants to announce its winter offers in November 2026. The distribution list “Regional customers” holds 620 contacts with the tag “customer”. Not all of them may receive the newsletter. The selection works out like this:
| Selection step | Removed | Remaining |
|---|---|---|
| Match the conditions | – | 620 |
| Without blocked contacts | 8 | 612 |
| Without excluded contacts | 4 | 608 |
| With a usable email address | 21 | 587 |
| Without unsubscribed or undeliverable addresses | 17 | 570 |
| With a permissible basis for the purpose | 241 | 329 |
| Each address only once | 9 | 320 |
Of 620 contacts, 320 receive the newsletter. The 241 contacts without consent stay out, even though they are recorded as customers. Management has examined the exception for customers and decided not to use it: for many of these addresses it cannot prove that it pointed out the option of refusing at the time of the sale. Instead, it asks about sign-up during advice meetings and adds a box that is not pre-ticked to the quote form (see Write a quote).
After the mailing, three people unsubscribe. Their addresses are blocked immediately; the distribution list now counts 317 addresses.
Checklist
- For every address there is consent with date, source and purpose (or the exception for customers has been checked and documented)
- Consent is tied to the purpose of the newsletter
- Sender correct (company name); as practice, postal address and imprint in the footer
- Unsubscribe link in every newsletter, one click is enough, free of charge
- Unsubscriptions take effect immediately and for all newsletters
- Privacy notice states identity, purpose, recipients and the measurement of opens
- Bounces and complaints block the address
- No purchased or researched addresses without consent
- Evidence can be produced if someone asks
How KMU | base helps
Sales | base connects consent, distribution lists and sending. It checks the technical side; whether your content, your sender and your consents are legally sufficient remains your responsibility.
1. Record consent. In the Sales menu, open Contacts, then the contact and the Marketing tab. Under “Legal bases and delivery blocks”, choose “Record basis”: address, purpose (for example newsletter), type of basis and evidence. Consent counts only with evidence (when, where and how it was given). Consent applies per address and purpose; unsubscriptions take effect immediately (“Consent per address and purpose, blocks, unsubscription, withdrawal”).
2. Check the sending policy. Under Marketing › Distribution lists, the “Sending policy” section sets which bases suffice for a purpose. The default is documented consent only. Customer relationship, registration or research do not count as consent; anyone who allows the customer relationship confirms this expressly and should document the legal basis.
3. Build distribution lists. You select recipients by tags or attributes such as customer, town or industry, and while compiling you see how many contacts match and how many will receive the newsletter (“Distribution lists by attributes with live counter”). Whether advertising is allowed is decided by the basis, not by the selection.
4. Design the newsletter. Under Marketing › Newsletters, you build the content from heading, subheading, text, image, button and divider and see beside it how it will arrive (“Newsletter with building blocks and live preview”). The template adds footer, imprint and unsubscribe link automatically; if the sender name, imprint or unsubscribe link is missing, the checklist reports it.
5. Approve and send. Only the approved version goes out (“Approval tied to the content, scheduling, pause/resume/cancel”). The recipients are fixed at the start (“Distribution list as tag expression, recipient count frozen at start”) and each address is checked again against its basis before every send. Bounces, complaints and unsubscriptions block the address immediately (“Bulk newsletter sending with feedback”).
6. Unsubscribing. Every newsletter contains an unsubscribe link in the footer and supports the one-click unsubscribe of email programs (“Only to addresses with consent, one-click unsubscribe”). Whoever opens the link confirms with one click on the unsubscribe page. The unsubscription applies to all purposes of that address. Unsubscriptions, complaints and deletion requests cannot be lifted.
Limits. Sales | base does not currently offer an automatic confirmation email (double opt-in); you record consents with evidence by hand or take them over during import when date and source are available. Sales | base cannot judge whether a mailing is “mass advertising”, whether the sender is correct or whether the exception for customers applies.
The details of operation are in the Sales | base guide. If you would like to try it yourself, take a look at the Demo or open a test account. If you have questions, we will help you via the contact page. You will find the terms under Pricing.
Sources
- Federal Act against Unfair Competition (UWG, SR 241), Art. 3, para. 1 lit. o, Art. 9, Art. 10, para. 1 and Art. 23, para. 1, as at 1 January 2025: fedlex.admin.ch (German original), accessed on 27.10.2026.
- Federal Act on Data Protection (DSG, SR 235.1), Art. 5 lit. a, Art. 6, paras. 3 and 6, Art. 19, Art. 30, para. 2 lit. b and Art. 60, para. 1 lit. b, as at 7 July 2025: fedlex.admin.ch (German original), accessed on 27.10.2026.
- Telecommunications Act (FMG, SR 784.10), Art. 45a, para. 1, as at 1 June 2026: fedlex.admin.ch (German original), accessed on 27.10.2026.
- Ordinance on Telecommunications Services (FDV, SR 784.101.1), Art. 83, para. 4, as at 1 July 2026: fedlex.admin.ch (German original), accessed on 27.10.2026.
- FDPIC: Advertising & marketing, section on advertising by email (page without a date), accessed on 27.10.2026.
- OFCOM: Spam (in German), published on 10 April 2019, accessed on 27.10.2026.
This guide does not replace legal or tax advice. Information as at 27.10.2026.