Bulk SMS in Germany: Consent, Sender ID and GSM-7 Guide
Bulk SMS Germany guide (SMS-Versand Deutschland): UWG consent, double opt-in, GDPR, alphanumeric sender ID, Telekom, Vodafone and O2 routes, umlauts.
By OmniChannels.ai Editorial Team · Reviewed by BroadNet Messaging Solutions Team
SMS & OTP
Short answer
To send bulk SMS in Germany, use a provider with routes to Telekom, Vodafone and O2, collect documented prior consent before any advertising SMS (German unfair-competition law and the GDPR), and use double opt-in to prove it. An alphanumeric sender ID of up to 11 characters works, with no formal Bundesnetzagentur registration. Umlauts and the sharp s fit GSM-7, so 160 characters per message is realistic.
On this page
- What rules apply to bulk SMS in Germany?
- Do you need consent to send advertising SMS in Germany?
- What is double opt-in and why does it matter for SMS?
- How do opt-out and the right to object work?
- How do sender names work in Germany?
- Which operators carry SMS in Germany?
- How should you handle OTP and transactional SMS?
- Do umlauts and the sharp s work in GSM-7?
- When should you send?
- A worked example: a Hamburg bakery chain
- What are the common mistakes?
- How OmniChannels.ai helps
Key takeaways
- Advertising by electronic means needs prior express consent under section 7 of the German Act against Unfair Competition (UWG), and the GDPR sets the standard for valid consent; plan for consent for every promotional SMS.
- Our regulation data names double opt-in as the operator-preferred standard for marketing, with the consent source, timestamp and channel logged per recipient.
- Germany has no formal Bundesnetzagentur sender ID registration in our data; operators white-list brands on a continuous basis. Alphanumeric IDs are up to 11 characters and numeric senders are preferred for transactional traffic.
- Three operators carry mobile traffic in our coverage data: Telekom Deutschland (262-01), Vodafone Germany (262-02) and Telefonica O2 (262-07), all with direct routes.
- The umlauts ä, ö, ü and the sharp s (ß) are in the GSM 7-bit alphabet, but German typographic quotation marks and the euro sign are not: the euro costs two characters and the quotes force Unicode.
This guide is for marketing, e-commerce, fintech and operations teams that want to send business SMS to German mobile numbers: OTPs, delivery alerts, appointment reminders and promotions. It covers who regulates what, how consent works, how sender names behave, which operators carry traffic and how German text affects message length. It is a practical overview, not legal advice. Confirm your set-up with German counsel before launch. (Kurz gesagt: Einwilligung zuerst, dann Versand.)
What rules apply to bulk SMS in Germany?
Three layers apply: competition law on advertising (UWG), data protection (GDPR and the German federal and state authorities) and operator policy. Telecom regulation sits with the Bundesnetzagentur (BNetzA), but it is not the body that decides whether your marketing SMS is lawful.
| Layer | What it covers | Where to check |
|---|---|---|
| UWG section 7 | When advertising by electronic means is an unreasonable nuisance | gesetze-im-internet.de |
| GDPR (DSGVO) | Lawful basis, consent quality, right to object | EUR-Lex |
| BNetzA and operators | Telecom regulation, routes, sender name handling | bundesnetzagentur.de |
Our regulation data lists BNetzA as the regulator and records the operators as Telekom, Vodafone and Telefonica O2.
Do you need consent to send advertising SMS in Germany?
Yes. Plan on prior express consent for every promotional SMS. Section 7(2) no. 2 UWG states that advertising by electronic mail without the addressee's prior express consent is always an unreasonable nuisance, and the GDPR requires consent to be freely given, specific, informed and unambiguous.
Section 7(3) UWG allows an exception for a business that obtained a customer's electronic address in connection with a sale. The text sets out conditions, all of which must be met:
- the address came from the customer in connection with a sale of goods or services;
- you use it for direct advertising of your own similar goods or services;
- the customer has not objected;
- the customer is told clearly, when the address is collected and at every use, that they can object at any time, at no cost other than the basic transmission rate.
The wording refers to an electronic postal address, and published guidance disagrees on whether SMS falls inside it. Several chambers of commerce say it does not, while some providers say it does. Do not build a programme on the exception. Collect SMS consent explicitly and ask counsel about edge cases.
What is double opt-in and why does it matter for SMS?
Double opt-in is a two-step sign-up in which the person first enters their number and then confirms it, for example by replying to a code or tapping a link. It matters in Germany because you must be able to prove consent, and a typed-in number could belong to someone else.
Our regulation data adds that consent source, timestamp and channel are logged per recipient and the confirmation timestamp is kept. A workable routine:
- Show clear wording at sign-up: who is sending, what kind of messages and how often.
- Send one confirmation SMS with a code or link, and treat the number as unconfirmed until it is used.
- Store the evidence: wording shown, date and time, channel, number and confirmation time.
- Do not bundle SMS consent into general terms and conditions.
- Honour objections immediately, and keep one suppression list across channels.
Our opt-in consent generator drafts wording, and the guide to opt-in consent across channels shows how to record it. See also the definitions of opt-in and opt-out.
How do opt-out and the right to object work?
Every recipient can object to advertising at any time, and you must make that easy. Article 21(2) and (3) GDPR give people the right to object to processing for direct marketing at any time, after which you must stop. Our data says the STOP keyword is honoured network-wide, is a one-step opt-out and holds until the person gives consent again, and that the required wording is in German.
In practice, add a short German line to every promotional message, such as "Abmelden: STOP an 12345" or a short link, and process replies within minutes, not days. Keep OTPs and service notifications separate so a marketing opt-out does not silence a login code.
How do sender names work in Germany?
Business SMS to Germany can use an alphanumeric sender ID of up to 11 characters or a numeric sender. Our data records no formal BNetzA registration, operator white-listing per brand on a continuous basis, and a preference for numeric senders on transactional traffic. The lead time column in our data reads "free-form", so treat any timing as set during onboarding.
| Choice | Strength | Limitation |
|---|---|---|
| Alphanumeric (up to 11 characters) | Shows your brand; good for promotions and alerts | Recipients cannot reply |
| Numeric long number | Supports replies; preferred for transactional traffic | Less brand recognition |
Draft the authorisation letter with our sender ID letter generator, check the current position with the sender ID checker or the Germany sender ID page, and read sender ID types explained. If you want us to prepare and file anything required with the operators, see registrations; decisions stay with the operators.
Which operators carry SMS in Germany?
Three mobile networks appear in our coverage data, each with a direct route:
| Operator | MCC-MNC |
|---|---|
| Telekom Deutschland | 262-01 |
| Vodafone Germany | 262-02 |
| Telefonica O2 | 262-07 |
Read delivery reports per operator rather than a blended rate, since one weak network can hide behind a healthy average. Our guide to improving SMS delivery rates explains how to diagnose gaps.
How should you handle OTP and transactional SMS?
Keep one-time passcodes, order updates and appointment reminders on their own sender and route, with no promotion inside. A mixed message is treated as advertising, which brings the consent rules above, and it puts your login codes at risk if marketing traffic is filtered.
| Traffic | Example | Practice |
|---|---|---|
| Transactional | OTP, shipping update, appointment reminder | No offers inside; numeric sender preferred; any hour |
| Promotional | Sale, new product, loyalty offer | Confirmed consent; German opt-out line; daytime schedule |
| Mixed | "Ihr Paket ist unterwegs. Jetzt 10 % Rabatt!" | Avoid; the offer makes it advertising |
For code length, expiry and wording see the OTP authentication messages guide. Our OTP service page covers delivery set-up.
Do umlauts and the sharp s work in GSM-7?
Yes. The letters ä, ö, ü, Ä, Ö, Ü and ß belong to the GSM 7-bit default alphabet (3GPP TS 23.038), so plain German fits 160 characters in one message and 153 per part when split. What breaks it is punctuation and symbols: German low-9 quotation marks („ and “), curly apostrophes and emoji are outside GSM-7 and move the whole message to Unicode with 70 characters (67 per part). The euro sign is available through the extension table but counts as two characters. See GSM-7 and concatenated SMS.
| Encoding | Single message | Per part when concatenated |
|---|---|---|
| GSM 7-bit | 160 characters | 153 |
| Unicode (UCS-2) | 70 characters | 67 |
These examples were counted against the limits:
| Message | Encoding | Characters | Parts |
|---|---|---|---|
Ihr Code: 482913. Gültig 10 Minuten. Bitte nicht weitergeben. Müller Bäckerei |
GSM-7 | 77 | 1 |
Müller Bäckerei: Zwei Brezeln zum Preis von einer, nur am Samstag! Details: mueller.example/s. Abmelden: STOP an 12345 |
GSM-7 | 118 | 1 |
Müller Bäckerei: Ihre Bestellung #1042 kommt morgen vor 17 Uhr. Straße prüfen: mueller.example/a |
GSM-7 | 96 | 1 |
Müller Bäckerei: Zwei Brezeln zum Preis von einer! Nur Samstag, ab 7 € pro Tüte. Abmelden: STOP an 12345 |
GSM-7 | 105 | 1 |
Müller Bäckerei: „Zwei Brezeln zum Preis von einer“ nur am Samstag! Abmelden: STOP an 12345 |
Unicode | 91 | 2 |
The fourth row stays one part but the euro sign costs two characters. The fifth row shows how German quotation marks switch a message to Unicode. Check final copy in the SMS character counter, and read SMS character limits and Unicode for other scripts.
When should you send?
We found no regulator-published time-of-day window for promotional SMS in Germany, and our regulation data records none. Agree sending hours with your provider, send promotions in local daytime (Central European Time, UTC+1, or UTC+2 in summer) and avoid late evenings. OTPs and alerts can go at any hour. The send time planner helps schedule campaigns, and SMS marketing rules by country compares hours across markets.
A worked example: a Hamburg bakery chain
"Müller Bäckerei" (synthetic) has 30 shops and wants pre-order confirmations, pickup alerts and a weekly offer.
- It collects consent at the till and in its app with double opt-in, storing wording, timestamp and confirmation time.
- Pickup alerts and OTPs use a numeric sender and plain GSM-7 text, with no offers inside.
- The weekly offer goes only to confirmed numbers, from an alphanumeric sender, with a German opt-out line and a daytime schedule.
- The copy avoids German quotation marks so each message stays at one part.
- Opt-outs from replies and the link feed a single suppression list that also covers email and WhatsApp.
What are the common mistakes?
- Relying on the existing-customer exception for SMS. Commentary disagrees, so get explicit consent.
- No proof of consent. A checkbox without a confirmation step is hard to defend.
- Bundled consent. Hiding SMS marketing in general terms is not specific consent.
- Offers inside OTPs or service messages, which turns them into advertising.
- Typographic quotes and emoji that double the part count.
- Ignoring per-operator reports, so a weak route goes unnoticed.
How OmniChannels.ai helps
OmniChannels.ai is powered by BroadNet, which has direct routes to Telekom, Vodafone and O2 in our coverage data. We support consent-aware campaigns with suppression handling, German and Unicode content, per-operator delivery reports and SMPP 3.4 for high volume, and we prepare and file any sender registration with you. For indicative list prices see the Germany SMS pricing page, then book a demo. Starting small? Read our SMS marketing guide for small businesses, or the France guide for a neighbouring market.
Frequently asked questions
Is bulk SMS legal in Germany?
Yes, for OTPs, service messages and consented marketing. Advertising SMS without prior express consent is treated as an unreasonable nuisance under section 7 UWG, and the GDPR applies to the processing of the phone numbers. Rules sit in several laws rather than one SMS statute, so have counsel review your sign-up flow.
Do I need double opt-in for SMS marketing in Germany?
The law asks for provable consent, not a particular method. Double opt-in, where the person confirms the sign-up by replying or clicking, is the common way to prove it, and our regulation data lists it as the operator-preferred standard. A checkbox alone leaves you unable to show who actually entered the number.
Can I text existing customers without consent?
Do not rely on it. Section 7(3) UWG contains a narrow exception for existing customers, but it is worded for electronic mail addresses and German commentary disagrees on whether it covers SMS. The safe route is to collect explicit SMS consent at the point of sale or sign-up, and ask a German lawyer about your case.
Do I need to register an alphanumeric sender ID in Germany?
Our data records no formal Bundesnetzagentur registration. Operators white-list sender names per brand on a continuous basis, and numeric senders are preferred for transactional traffic. BroadNet confirms the current requirement during onboarding, so test your sender name on Telekom, Vodafone and O2 handsets before launch.
Do German umlauts need Unicode?
No. The letters ä, ö, ü, Ä, Ö, Ü and ß are part of the GSM 7-bit default alphabet, so a plain German message fits 160 characters. German low-9 and high-6 quotation marks, curly apostrophes and emoji are not in GSM-7 and switch the whole message to Unicode with a 70-character limit.
Is there a legal sending time window for promotional SMS in Germany?
We found no regulator-published time-of-day window for promotional SMS in Germany, and our regulation data records none. Send promotions in local daytime, avoid late evenings and Sundays out of courtesy, and keep OTPs and alerts on a transactional route that can run at any hour.
Sources
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