About Onoff

Onoff combine telecom infrastructure with software agility to build simple, powerful, and

borderless communication experiences.

As we scale our telecom operations internationally, we are looking for a Product Manager Voice

Calls & Numbering to help shape and operate the core telecom services powering our customers'

experience.

The role

Voice calls and phone numbers are at the heart of Onoff's value proposition.

As Product Manager Voice Calls & Numbering, you will own the performance, evolution, and operational excellence of our voice and numbering services.

You will work at the intersection of telecom operations, product, engineering, legal, finance, and carrier partnerships to ensure our customers can call, receive calls, and use their phone numbers seamlessly across multiple markets.

This is a highly cross-functional role with significant exposure to telecom operations, partner management, business decision-making, and product strategy.

You will initially focus on execution and coordination, while progressively gaining ownership over strategic decisions and partner relationships.

This role can be based in Paris (France), Tallinn (Estonia), or Bucharest (Romania).

What you'll do

Voice & Numbering Operations

• Monitor and improve voice service performance and reliability.

• Coordinate incident resolution and service recovery during operational issues.

• Contribute to voice routing optimization and service quality improvements.

• Support the evolution of VoIP, VoLTE, roaming and future telecom services.

• Participate in numbering strategy and number resource management.

Partner & Supplier Management

• Work with telecom operators, carriers, and international partners.

• Coordinate technical and operational projects with suppliers.

• Participate in commercial discussions, SLA monitoring, and service reviews.

• Support pricing analysis and cost optimization initiatives.

Cross-functional Coordination

• Collaborate closely with Engineering, Product, Legal, Finance, Customer Care, and Operations teams.

• Ensure telecom services are delivered and evolved efficiently.

• Contribute to regulatory and compliance-related topics.

• Drive troubleshooting initiatives and root cause analysis.

Product & Innovation

• Monitor telecom market evolutions and emerging technologies.

• Contribute to the future roadmap of voice and numbering services.

• Help shape the next generation of mobile communication services at Onoff.

What we're looking for

Experience

• 3–5 years of experience in telecom, telecom product management, telecom operations, carrier relations, or a related field.

• Experience working with operators, MVNOs, MVNEs, telecom providers, or CPaaS companies.

• Exposure to voice services, telecom infrastructure, numbering, interconnection, or carrier environments.

Skills

• Strong coordination and stakeholder management skills.

• Ability to navigate both technical and business discussions.

• Strong problem-solving mindset and interest in incident management.

• Comfortable working with numbers, costs, and business impact.

• Curious and willing to understand how things work end-to-end.

• Excellent communication skills.

Languages

• Fluent English is mandatory.

Nice to have

• Knowledge of VoIP, VoLTE, IMS, roaming, or interconnection ecosystems.

• Experience in MVNO or telecom service environments.

• Exposure to telecom regulations and numbering constraints.

• Experience working in international telecom environments.

Why join Onoff?

• Join a fast-growing European telecom and SaaS company.

• Play a key role in the launch of Onoff Mobile.

• Work directly with experienced telecom leaders and accelerate your learning curve.

• Gain exposure to product, operations, partnerships, business, and strategy.

• Build expertise in one of the most complex and evolving industries.