Slovakia regulatory framework

RÚ SR in practice: numbering, sender ID and STOP for SMS in Slovakia

RÚ SR (Regulatory Authority for Electronic Communications and Postal Services) supervises Slovak mobile numbering and A2P duties towards four local carriers: Slovak Telekom (Magenta), Orange Slovensko, O2 Slovensko and 4ka. 4notify delivers SMS to +421 numbers via tier-1 international A2P gateway, preserving alphanumeric sender ID, automatic STOP/HELP handling and full delivery audit trail.

The four Slovak mobile carriers

Slovak Telekom (Magenta)

Prefixes: +421 901 · +421 902 · +421 903 ...

Largest carrier, DT Magenta group, ~38% market

Fastest sender ID approval (2-3 days).

Orange Slovensko

Prefixes: +421 908 · +421 909

Second-largest, Orange France group, ~31% market

Conservative on alphanumeric IDs.

O2 Slovensko

Prefixes: +421 910 · +421 911

Third, PPF group, ~22% market

Good sender ID acceptance.

4ka

Prefixes: +421 940 · +421 941 · +421 942 ...

MVNO since 2014, ~9% market — lowest pricing

MVNO on O2 Slovensko infra.

RÚ SR numbering plan

+421 901-907 xxxxxxxSlovak Telekom — mobile
+421 908-909 xxxxxxxOrange Slovensko — mobile
+421 910-911 xxxxxxxO2 Slovensko — mobile
+421 940-944 xxxxxxx4ka — MVNO mobile
+421 2 xxxxxxxBratislava — landline
+421 41 xxxxxxxŽilina — landline
+421 55 xxxxxxxKošice — landline
+421 51 xxxxxxxPrešov — landline

5-step RÚ SR compliance flow

  1. 01

    Register sender ID with tier-1 gateway

    Sender ID (up to 11 chars) registered once. Commercial documentation required (Slovak IPO or EU TM). Slovak Telekom whitelists in 2-3 days; Orange and O2 5-7.

  2. 02

    Enable STOP / NEPOSIELAJTE keyword

    Per RÚ SR rules, every A2P sender must recognise STOP, NEPOSIELAJTE, PRESTAŇTE, HELP. 4notify handles automatically.

  3. 03

    HLR lookup and per-operator DLR

    Before dispatch HLR identifies current carrier (~35% portability). Per-operator reason code DLR.

  4. 04

    Compliance with Law 452/2021 + GDPR

    Law 452/2021 and Personal Data Protection Law 18/2018 require opt-in for marketing; soft opt-in for existing customers.

  5. 05

    Per-operator latency monitoring

    Typical P50: Slovak Telekom 2.2s, Orange 2.4s, O2 2.5s, 4ka 2.8s.

FAQ

What are RÚ SR fines for SMS spam?

Law 452/2021 allows fines up to €1,000,000. In parallel, ÚOOÚ can impose GDPR fines.

How long does sender ID activation take?

Overall 2-7 business days. Slovak Telekom typically 2-3; Orange and O2 5-7.

Does portability work in Slovakia?

Yes. Since 2003 under RÚ SR. Today ~35% have switched. 4notify HLR refresh every 12h.

Is there a do-not-call register in Slovakia?

Not centralised. 4notify maintains an internal per-sender STOP database.

Start free

Full RÚ SR compliance, sender ID in 2-7 days, sk/en support.