AI phone assistant or external telephone service? A comparison for SMEs

An external telephone service (office service, secretarial service) answers calls with real people and forwards messages. An AI phone assistant works around the clock, is directly connected to the calendar and CRM, and handles standard requests independently, instead of just logging them. Which solution is more suitable depends on how standardized your calls are and how much tact they require.

Comparison at a glance

• Availability: Telephone service during agreed hours, often with an additional charge for evenings and weekends – AI assistant around the clock, without surcharges.
• Parallel calls: Depending on staffing levels in telephone service – the AI assistant handles multiple calls at the same time.
• Call outcome: Telephone service usually leaves a note by email – the AI assistant books the appointment or creates the case directly in the system.
• Company knowledge: Telephone service knows your company only from a call script – the AI assistant accesses a maintained knowledge base.
• Empathy and special cases:People are clearly at an advantage here, for example in complaints or sensitive conversations.
• Cost logic: Telephone service is usually billed per call or per minute – an AI assistant usually involves setup plus ongoing usage costs. The cost drivers are explained What does an AI phone assistant cost?.

When an external telephone service is the better choice

• Most calls are individual, emotional, or require negotiation skills.
• Callers explicitly expect a human, for example in an exclusive advisory situation.
• There are no systems that an assistant could usefully be connected to – then even with an AI assistant, only a note remains.

When an AI phone assistant is the better choice

• A large share of calls are repetitive: appointments, opening hours, status questions, requests for a callback.
• Many calls come in outside business hours or during peak times – see Calls outside business hours.
• Results should land directly in the calendar, CRM or ticketing system instead of the email inbox.
• Calls come in multiple languages – one assistant speaks them all, see multilingual AI phone assistant.

The combination: AI first, humans for exceptions

In practice, a division of labor: the AI assistant answers all calls, handles standard requests, and passes special cases on to your team with a summary — or to a telephone service if no one is available internally. This keeps people focused where they make the difference.

How to make the decision

1. Categorize calls for two weeks: standard, individual, emergency.
2. Check which standard requests an assistant could handle directly via an interface.
3. Start with a pilot for a clearly defined area and compare metrics.

How an assistant works with your systems is shown on the page AI phone assistant. The Introduction of an AI phone assistantcan be funded as a consulting project: Through INQA-Coaching the federal government covers 80% of coaching costs nationwide. The funding applies to the support provided, not the software itself. The funding check shows in just a few minutes what is eligible for your business.

Comparison table at a glance

• Criterion – telephone service – AI phone assistant
• Availability – agreed times – around the clock
• Parallel calls – depending on staffing – many at the same time
• Result – note by email – completed case in the system
• Company knowledge – call script – maintained knowledge base
• Empathy in special cases – high – limited, handover to humans
• Multilingualism – depending on staff – many languages
• Scaling during peaks – staffing issue – technically uncritical

What about the answering machine and the call center?

The answering machine is the cheapest solution, but many callers do not leave a message, and the messages are often incomplete – more in comparison AI phone assistant or answering machine?. A large call center is rarely worthwhile for SMEs; it is designed for high volumes and standardized campaigns. An outlook on how the role of call centers is changing is provided by Why AI phone assistants are changing call centers.

Calculation instead of gut feeling

Instead of comparing prices as a flat rate, calculate with your own numbers: calls per month, share outside business hours, share of standardized inquiries, and average call duration. This shows what a telephone service would cost under per-minute or per-call billing — and how many calls an assistant could handle without follow-up work. The framework for this is provided by the Automation Calculator.

From our projects

In our own projects, the same pattern keeps emerging: the value comes less from the voice than from the clear task. At Blumenhaus am Pfaffenteich the assistant takes orders while customers are being advised in the store; at easy Parken it answers questions about opening hours and rates; at ELLI buspassengers book their ride directly by phone.

In none of these cases was it about displacing people from the phone — it was about ensuring that customers can still reach someone even when the team cannot.

Decision support in five questions

1. How many calls are standard?The higher the share, the stronger the case for an AI assistant.
2. When do the calls come in?Many calls in the evening or on weekends argue against solutions limited to office hours.
3. What should happen in the end?Just a note — or a booked appointment, a case created?
4. How sensitive are the conversations?Many emotional calls argue for people on the phone.
5. Which languages do your callers speak?Multilingualism is significantly easier with AI.

Data protection compared

An external telephone service also processes personal data on behalf of the client and requires a data processing agreement. With the AI assistant, questions about speech recognition, the language model, and storage locations are added. Both variants can be operated in compliance with data protection regulations – the key factors are contracts, processing locations, and deletion periods. Details: AI phone assistant and GDPR.

Frequently Asked Questions

Is an AI phone assistant cheaper than a telephone service?

That depends on call volume and billing. For many standardized calls and 24/7 availability, an AI assistant is often more cost-effective because there are no surcharges for off-peak hours and requests are handled directly.

Can an AI phone assistant completely replace a telephone service?

For mostly standardized calls, often to a large extent. For complaints, sensitive conversations, and special cases, a human remains useful — internally or externally.

Do callers notice that they are speaking with an AI?

They should notice it: The EU AI Act requires that people are informed when they are interacting with an AI. A brief announcement at the start is standard and is accepted by most callers.

Can I combine an AI phone assistant and a telephone service?

Yes. The assistant answers all calls and handles standard requests; special cases are forwarded with a summary to your team or to an external telephone service.

As of October 2026.