“What does an AI phone assistant cost?” is the most common question in the initial conversation, and the answer is worth breaking down concretely instead of dismissing with “it depends”.
The cost components
| Cost component | Typical range | What’s included |
|---|---|---|
| Setup (one-time) | from €1,997 | building the knowledge base, aligning the conversation script, test phase, connecting the phone number |
| Ongoing operation | €297–397/month | per quote, scope see pricing |
| Per-minute cost | set in the quote | language-model and voice-synthesis cost per conversation minute |
| Maintenance & adjustments | per quote, scope see pricing | maintaining new prices, new services, changed rules in the knowledge base |
| With system integration (ERP, calendar) | €2,500–4,500 once, then €590–790/month | one system integration (ERP, calendar or invoicing) plus one automated process |
What drives the price
Three factors determine where you land in the range: call volume (more conversations mean more language-model minutes), the complexity of the knowledge base (simple scheduling is cheaper than an assistant that needs to know your entire service list with special cases), and the depth of system integration (just taking a message is cheaper than writing directly into your ERP with order creation).
An assistant that just takes calls and sends a summary email sits at the lower end. An assistant that books appointments directly into your calendar, creates orders in the ERP and handles several escalation rules sits at the upper end, but it also takes on correspondingly more work.
Hidden costs at cut-rate providers
With unusually cheap offers, a second look at the fine print is worth it. Common hidden costs:
- Knowledge-base upkeep extra: the base price looks low, but every change to prices or services is billed separately.
- No real ERP write access: the assistant takes calls but only forwards them as an email; the actual data entry remains manual work.
- Per-minute price with no cap: during a promotion or seasonal peak, the bill can unexpectedly explode if no cap is defined.
- GDPR documentation unclear: ask any provider up front whether the data processing agreement and deletion processes are included in the price or negotiated afterward.
Comparison to an answering service and an in-house employee
An external answering service usually bills per call or per minute; as volume rises, costs rise linearly with it. A part-time employee just for answering the phone costs, at a rough estimate, from about €800–1,500 per month including payroll overhead, but isn’t available 24/7 and can’t handle any number of calls in parallel. The costs of the three options grow differently with call volume. So compare them against your own volume.
Worked example
According to its call log, a trade business misses 2 calls a day, so 40 a month at 20 working days. We apply 5 % to that, which makes 2 jobs. The 5 % is not a measured industry rate but a deliberately low floor. At an average job value of €750, that is €1,500 in revenue. The calculation uses margin, though: at a contribution margin rate (Deckungsbeitragssatz) of 30 % (an assumption, if you don’t know your own), the business misses €450 a month. All of these are example values, not industry figures.
In this example, the €450 is what the business is missing, not what an assistant wins back. With your own numbers the result can look quite different. How the calculation works step by step is explained in our article Missed calls in the trades, where you can also run it with your own numbers. If the total across that self-check stays below €500 a month, automation isn’t worth it yet.
If you’d like to put your result into context afterwards, book a free initial call (30 minutes, a first assessment).