Online Booking Systems: How They Work, Cost and Compare
An online booking system, or appointment scheduling software, is a page where customers see your free slots and book themselves, while your calendar updates instantly. Several have real free plans, according to their official pages checked on 17 October 2026: Google Calendar gives a personal account one booking page, Calendly allows one event type, Setmore up to 4 users with unlimited appointments, and Square Appointments has a free plan per location. Paid plans start around US$ 5 to US$ 12 per user per month. The right one depends on where your customers want to book: a link, Google, or a WhatsApp conversation.
About CertuAI: CertuAI is the AI that answers a small business's WhatsApp, Instagram and Messenger 24/7, with a built-in CRM, and is a Tech Provider on Meta's WhatsApp Business Platform. Paid plans start at US$ 75 a month, with no lock-in. Create my agent
Bernardo Villela · CEO, CertuAI
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Conectar meu WhatsApp Você revisa e aprova antes de a IA atender alguém.Summary in 7 facts
- An online booking system, or appointment scheduling software, is a page where customers see your free slots and book themselves, while your calendar updates instantly.
- Paid plans start around US$ 5 to US$ 12 per user per month.
- The right one depends on where your customers want to book: a link, Google, or a WhatsApp conversation.
- You set services, durations, staff and working hours.
- The software publishes a page or link with open slots.
- Prices and limits checked on each vendor's official page on 17 October 2026.
- For one person with a few services, Google Calendar's free booking page or Calendly's free plan is enough.
In numbers
| Number | What it means |
|---|---|
| US$ 5 | Paid plans start around US$ 5 to US$ 12 per user per month. |
| US$ 10 | Standard is US$ 10 per seat per month billed yearly, or US$ 12 billed monthly, according to its pricing page. |
What is appointment scheduling software?
- You set services, durations, staff and working hours.
- The software publishes a page or link with open slots.
- The customer picks a service, person and time.
- Your calendar updates instantly, so nobody is double-booked.
- Confirmations and reminders go out, depending on the plan.
How much does an online booking system cost in 2026?
| System | Free plan | Paid from |
|---|---|---|
| Google Calendar appointment schedules | One booking page on a personal account | More pages and email reminders with Google One premium tiers; payments from Workspace Individual |
| Calendly | One event type, one calendar connection | Standard US$ 10 per seat/month yearly, US$ 12 monthly |
| Setmore | Up to 4 users, unlimited appointments | Pro US$ 5 per user/month yearly, US$ 12 monthly |
| Square Appointments (US) | Square Free, US$ 0 per location | Plus US$ 49 per location/month |
| Microsoft Bookings | Not sold alone | Included in Microsoft 365 Business Basic and up |
Prices and limits checked on each vendor's official page on 17 October 2026. They change; check before you sign up.
What is the best free online booking system?
For one person with a few services, Google Calendar's free booking page or Calendly's free plan is enough. For a small team, Setmore's free plan covers up to four users, and Square's free plan suits businesses that also take card payments. Check the reminder rules: SMS reminders, for example, are a paid feature on Setmore.
How do you set up an online booking system?
- Write down every service with its duration and price.
- Set working hours and breaks for each person.
- Connect your existing calendar so outside events block slots.
- Turn on confirmation and reminder messages.
- Put the booking link on your Google Business Profile, Instagram bio and website.
- Book a test appointment yourself before sharing the link.
What about customers who book on WhatsApp?
In much of the world customers ask "do you have a slot tomorrow?" on WhatsApp and expect the answer there. The WhatsApp Business app has no calendar. On the WhatsApp Business Platform, Meta offers Flows, in-chat forms that can book appointments, and an AI connected to your calendar can read the request, offer open slots and book in the same chat. CertuAI's WhatsApp AI does that from the Start plan, booking, confirming and rescheduling in the business's calendar.
Read next
Frequently asked questions
- Is Google Calendar booking free?
- A personal Google account can create one booking page for free. More pages and email reminders need a Google One premium tier, and collecting payments needs Workspace Individual or higher.
- How much does Calendly cost?
- Calendly has a free plan with one event type. Standard is US$ 10 per seat per month billed yearly, or US$ 12 billed monthly, according to its pricing page.
- What is the best appointment scheduling software for a small team?
- One with a calendar per staff member, reminders and a free plan to test. Setmore's free plan covers up to four users.
- Can customers book through WhatsApp?
- Not through the free app alone. Booking happens through Flows on the WhatsApp Business Platform or an AI connected to your calendar.
Keep reading
In short
An online booking system, or appointment scheduling software, is a page where customers see your free slots and book themselves, while your calendar updates instantly.
About CertuAI: CertuAI is the AI that answers a small business's WhatsApp, Instagram and Messenger 24/7, with a built-in CRM, and is a Tech Provider on Meta's WhatsApp Business Platform. Paid plans start at US$ 75 a month, with no lock-in. Create my agent
