Build-your-own platforms
Looking for a Retell AI alternative?
Developer platform for building real-time voice agents.
Written by the Silux Voice team, so read it knowing that — which is why the section on where Retell AI is better is just as long as it needs to be. Competitor prices are as we found them and dated; check their site before you decide.
Silux Voice
from £24.99/mo
- Starter £24.99 — 250 minutes
- Growth £49.99 — 600 minutes
- Professional £99.99 — 1,400 minutes
- Overage 6p (Starter) / 5p a minute
- 14-day free trial, 30 minutes, no card · no setup fee, no contract
Same numerals in £, € and $ — never currency-converted.
Retell AI
$0.07–$0.31/min
Pay as you go, $0.07–$0.31 a minute all-in depending on the models chosen, plus $2/mo per number.
Checked Sep 2026 on retellai.com/pricing · prices in USD
Where Silux Voice is the better fit
- ✓A finished receptionist you set up in minutes — nothing to build or host
- ✓A plain monthly price: 250 minutes for $24.99
- ✓Takes phone orders — anything not on your menu is noted as a special request for you to confirm, never refused and never promised
- ✓Books straight into Calendly, Acuity, Cal.com, SimplyBook.me, Setmore or Microsoft Bookings
- ✓Texts a confirmation with the customer’s own change-or-cancel link, sends reminders and offers cancelled slots to people waiting for one with its Open slot notifier
Where Retell AI is the better fit
- ★Full developer control — build any voice agent you like
Where you’ll find them level
- ≈ Both offer a public developer API
Feature by feature
“Not stated” means we couldn’t find it on Retell AI’s own pages — not that they can’t do it.
| Capability | Silux Voice | Retell AI |
|---|---|---|
| Takes phone orders on the call | Yes | Not stated |
| Items not on your menu taken as special requests for you to confirmNever refused, never promised — you confirm it. | Yes | Not stated |
| Repeat-prescription requests for pharmaciesMedicines, name and date of birth; never gives medical advice or confirms stock. | Yes | Not stated |
| Checks your Google or Outlook calendar live on the call, two-way | Yes | Not stated |
| Books into Calendly, Acuity, Cal.com, SimplyBook.me, Setmore, Microsoft Bookings | Yes | Not stated |
| Confirmation text with the customer’s own change-or-cancel link | Yes | Not stated |
| Open slot notifier — cancelled slots offered to people waiting for one | Yes | Not stated |
| Knowledge categories auto-trained from your websiteYou approve what it learns; weekly re-check on Growth and above. | Yes | Not stated |
| You choose what it says when it doesn’t know | Yes | Not stated |
| Voice cloning — your own voice, or one you have written permission to useSilux Voice: Growth and above. | Yes | Not stated |
| Human receptionists as backupWe have none — this is a real reason to choose a hybrid service. | No | Not stated |
| Public developer API | Yes | Yes |
| WhatsApp conversations and remindersSilux Voice: Growth and above; each message type switches on or off. | Yes | Not stated |
| Prices published on the website | Yes | Yes |
Competitor information from their public pages, checked Sep 2026. Silux Voice rows are what we ship today. See the full matrix.
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Receptionist for HVAC contractors
When the AC dies in July, the customer calls four contractors and books with the first one who picks up. If your office is on a job site, that's not you.
Receptionist for plumbers
A burst pipe at 6pm is an emergency for the customer and a booked job for you — but only if someone answers. Under a sink, you can't, and the caller dials the next plumber on Google.
Receptionist for electricians
Fault-finding, a dead consumer unit, a tripping circuit — the customer wants it fixed today. If you're mid-install and can't pick up, that booked job goes to the next sparky.
Try Silux Voice free
14 days and 30 minutes of answering. No card needed.