ONOFF TELECOM SAS

ONOFF TELECOM SAS operates the Onoff consumer second-number app and Onoff Business telephony platform, turning French and international numbering into cloud services. Public identity is solid via SIREN 832 235 253 and first-party terms, with a limited but visible RIPE/BGP footprint under AS211948. Two gaps define the assessment: ARCEP numbering decisions reference a different SIREN, and company‑reported scale metrics are inconsistent. Watch the regulatory entity mapping, API surface governance, and carrier‑dependency signals.

ONOFF TELECOM SAS

ONOFF TELECOM SAS is a Paris-based cloud telecom operator that transforms regulated telephone numbers into consumer and business telephony services, concentrating control over number assignment, communications data, and programmable integrations, and thereby creating material dependency for its European customers.

Why It Matters

Operational decisions at ONOFF TELECOM—such as number revocation, API access changes, or carrier transitions—can disrupt business communications, alter data flows into CRM platforms, and affect consumer reachability across multiple countries. The visible internet-routing footprint is small but acts as a canary for service-layer reachability, while the ARCEP regulatory context ties numbering rights to a legal entity that may not perfectly match current registration records, introducing potential compliance exposure.

What Public Sources Show

ONOFF TELECOM SAS is a Paris-based telecom operator that transforms regulated telephone numbers into cloud services. Through its Onoff consumer app and Onoff Business platform, the company sells secondary phone numbers and business telephony to customers across Europe. Its control over number assignment, communications data, and programmable interfaces makes it a single point of dependency for reachability, call routing, and enterprise integrations.

Any operational change here ripples directly into the personal and corporate communications fabric that relies on its numbers staying active and accessible.

The French state company directory confirms ONOFF TELECOM as active SIREN 832 235 253, a simplified joint-stock company created in 2017 and headquartered on Boulevard de Bonne Nouvelle in Paris. The company’s own terms identify it as the developer of the Onoff application and an ARCEP-recognised operator. It also maintains offices in Tallinn, and states that more than two billion messages have been exchanged through its technology.

RIPE records list the firm as an Internet number resource member, and a small public routing footprint appears under AS211948.

The consumer product, marketed as Onoff, provides a French mobile number with calls, SMS, voicemail, and call-forwarding on a single smartphone without a second SIM. Onoff Business extends that into team telephony, selling per-license plans that bundle mobile and web apps, Microsoft Teams calling, call recording, transcription, IVR, and CRM integrations.

Both consumer and business users depend on the operator to provision and maintain their numbers, and the business product adds a Management Console through which administrators assign numbers to employees and govern service access.

ONOFF TELECOM’s control surface reaches well beyond number provision. The business service defines telephone numbers as national numbering-plan resources assigned via its Management Console, giving the company and its business customers joint control over the lifecycle of each number. The platform also handles calls, SMS, voicemails, recordings, transcriptions, and reporting, making communications metadata and content part of its operational envelope.

A webhook and beta REST API allow call, SMS, and user-management data to flow into customer CRMs and internal systems, creating a programmable integration surface that is gated by plan tier and authentication.

This architecture means that ONOFF TELECOM’s decisions can cascade into enterprise operations. A change in API availability, a contract-enforcement action such as account suspension, or a failure in an upstream mobile-operator relationship could sever an employee’s phone number, wipe historical call records, or break a CRM integration. For consumers, a revoked secondary number can disrupt verification codes, authentication channels, and long-standing contact points.

The business terms explicitly permit the company to request identity documents and to delete non-compliant accounts, underscoring its unilateral enforcement power.

A critical gap exists in the mapping of regulated numbering resources. ARCEP decisions related to “Onoff telecom” carry SIREN 799 270 160, while the current ONOFF TELECOM SAS is registered under SIREN 832 235 253. Public records do not clarify whether the historical number blocks were transferred, are held by a related entity, or are still operational under the present legal vehicle.

Until that link is confirmed, any claim that the current company directly controls a specific ARCEP-assigned block should be treated as plausible but unverified.

Several watchpoints merit attention. Resolving the SIREN mismatch with ARCEP would clarify which numbering blocks the company truly controls. Infrastructure observers should monitor AS211948 for new upstreams or withdrawn prefixes as a canary for service changes. Enterprise risk managers should track the Onoff Business API surface and contract terms, because adjustments to webhooks, authentication, or account enforcement can abruptly alter data access.

Finally, the company’s own marketing claims about country coverage and message volume should be verified against external benchmarks, as they have not remained consistent across official pages.

Operating Surface

ONOFF TELECOM SAS operates Onoff, a consumer secondary-number app, and Onoff Business, a business telephony platform. Through these products it assigns and manages National Numbering Plan mobile numbers, handles calls, SMS, voicemail, and recordings, and exposes webhook and API integration points. Its public infrastructure identity is tied to RIPE NCC membership and the AS211948 routing footprint.

The company is tracked because it mediates a critical link between regulated telephone numbering and cloud-subscription services. For businesses it controls employee number assignment, communications metadata, and API conduits into internal systems. For consumers it gates secondary-number availability and continuity. Dependency on a single operator for these functions creates concentration risk, particularly around account enforcement, carrier outages, and governance of the programmable interface.

Watchpoints

ONOFF TELECOM’s value proposition lies in abstracting regulated numbering into a programmable cloud service; that abstraction also concentrates operational risk. The company’s public footprint is intentionally small as an internet network, but its real leverage comes from the number lifecycle and API integrations it controls for business customers. Monitoring the SIREN mismatch and carriage dependencies is the most direct way to gauge regulatory and operational resilience.

ARCEP SIREN reconciliation, AS211948 routing changes, Onoff Business API and webhook modifications, and contract‑enforcement updates are the highest‑priority observables. A shift in any of these would materially alter the dependency profile.

The precise relationship between current ONOFF TELECOM SAS (SIREN 832 235 253) and the historical Onoff telecom (SIREN 799 270 160) numbering rights is not publicly documented. Additionally, carrier contracts, wholesale numbering arrangements, and independent customer‑count verification remain absent from open sources.

Sources

• Registry RDAP / WHOIS record - public-source identity and registry context for ONOFF TELECOM SAS.
• annuaire-entreprises.data.gouv.fr - Lists ONOFF TELECOM as active SIREN 832 235 253, SAS, other telecommunications activities, created 2017-09-13, headquartered at 26 boulevard de Bonne Nouvelle in Paris, with 20 to 49 employees in 2023.
• onoff.app - Identifies ONOFF TELECOM as a simplified joint-stock company registered in Paris under number 832 235 253 and says it developed the ONOFF application for secondary contact management and communications services.
• business.onoff.app - Defines ONOFF TELECOM as registered under number 832 235 253, operating in telecommunications, and defines the Management Console, number assignment and company-user account controls for Onoff Business.
• support.onoff.app - Describes Onoff as a telecommunications operator based in Paris and Tallinn that lets users have several phone numbers of different nationalities on one smartphone without a second SIM or another mobile.
• onoff.app - Describes the consumer second-number app, pricing starting point, features such as French mobile number, calls, SMS/MMS, voicemail, on/off mode, app support, call forwarding and caller-ID hiding, and states that Onoff Telecom is recognized by ARCEP.
• onoff.app - States that Onoff is owned by Onoff Telecom, uses patented cloud-number technology, has offices in Paris and Tallinn, supplies numbers internationally, and has reported more than 2 billion messages exchanged using its technology.
• business.onoff.app - Describes Onoff Business as a business telephony solution with management interface, employee number assignment, mobile and web applications, Microsoft Teams calling, plan tiers and features including recordings, transcription, integrations, IVR and AI call tools.
• docs.onoffbusiness.com - Documents Onoff Business webhooks for call, SMS, voicemail and call-recording data, and the beta REST API for user, number, department and statistics management.
• RIPE registry record - Lists ONOFF TELECOM SAS as a RIPE NCC member at 26 Boulevard de Bonne Nouvelle, Paris, with serviced areas in BE, DE, EE, ES, FR, GB and IT.
• bgp.he.net - Shows AS211948 as ONOFF-FR / ONOFF TELECOM SAS and mirrors RIPE aut-num details including organization ORG-OTS22-RIPE, creation on 2025-03-05, and visible upstreams in public BGP collection.
• arcep.fr - ARCEP decisions found for the Onoff telecom name assign or transfer numbering resources, but the decisions reviewed use SIREN 799 270 160, requiring legal-entity caveating against current ONOFF TELECOM SAS SIREN 832 235 253.