FAQ · 2026-08-13
Booking system cost: SaaS tool vs. custom build (UK)
Third-party booking tools charge you monthly, forever. A custom booking system built into your own site costs more upfront and then nothing extra. Here's how the numbers actually compare.
If you're weighing up adding online booking to your website, the choice usually comes down to two very different cost shapes: pay a small amount every month forever, or pay more once and be done with it. Neither is automatically the right answer. It depends on how central booking is to your business.
What a SaaS booking tool costs
Third-party tools like SimplyBook, 10to8, or BookingLive typically run from free up to around £30 a month, with most small businesses landing somewhere in the £10-30/month range once they need more than the most basic plan. That's a low barrier to entry. You can be taking bookings within a day, with no upfront build cost.
The catch is it's a cost that never stops. £20 a month doesn't sound like much, but across a few years it adds up to more than most small custom builds would have cost outright, and you're renting the functionality rather than owning it.
What a custom-built system costs
leeday.uk's Custom tier, which covers bespoke functionality like a booking system built into your own site, starts from £4,000+. That's a much bigger number upfront. What you get for it is a system built specifically around how your business actually takes bookings, integrated properly with your existing site rather than sitting on top of it, and no separate ongoing fee for the booking functionality itself once it's built.
Working out which one makes sense
If you're not sure yet whether online booking will actually get used, or your booking volume is genuinely low, a SaaS tool is the sensible way to find out. It's cheap to try, easy to cancel, and doesn't commit you to anything.
If booking is core to how your business runs (you're already fielding most enquiries as booking requests, or you know it's going to be a permanent fixture) the maths starts to favour a custom build. Run the SaaS monthly fee out three or four years and compare it to a one-off custom cost, and the custom build often works out cheaper over that stretch, on top of being built exactly around your process rather than a generic template.
What a custom build gets you that a generic tool usually doesn't
Integration with calendars, payment systems, and other tools you already use, without working around the limits of someone else's platform. A booking flow that matches how your site actually looks and works, not a widget that feels bolted on. And no risk of a SaaS provider changing their pricing or features out from under you later.
If you're still deciding whether your site needs a booking form at all, or just a contact form, should my website have a contact form, booking form, or both is worth reading first.
For the full breakdown of what's included in a custom build, website design & build covers the Custom tier and what it's typically used for.
Frequently asked questions
How much do third-party booking tools cost?
Most run somewhere between free and £30 a month depending on features and booking volume, with better plans typically £10-30/month. It's an ongoing cost that continues for as long as you use the tool.
How much does a custom-built booking system cost?
leeday.uk's Custom tier, which covers custom functionality like booking systems, starts from £4,000+ as a one-off build. There's no separate monthly fee for the booking functionality itself after that, though standard hosting/support costs still apply.
Which one actually makes sense for a small business?
A SaaS tool makes sense if you're testing whether online booking helps at all, or your volume is low enough that a small monthly fee is genuinely cheaper than a custom build over time. A custom system makes more sense once booking is core to how the business runs and you'd rather own it outright.
Can a custom booking system integrate with what I already use?
Usually yes, calendars, payment systems and existing tools can be connected as part of a custom build, built specifically around how your business actually takes bookings rather than fitting your process into a generic tool.
Topics: Website Improvements, Small Business, Guide
By Lee Day · leeday.uk · UK-wide support