At 10 to 20 people, a spreadsheet can no longer keep up with real approvals, clashes and accurate balances. A dedicated tracker is the right tool, and our pick is Book Time Off at a flat £1 per user / month: self-service requests, one-click approvals, a maximum-absent limit so too many people cannot be off at once, automatic UK bank holidays, and a shared calendar every manager can see. A team of 20 is £20 a month, with a 30-day free trial and no card.
What changes between 10 and 20
The job itself does not change, but the volume and the cost of mistakes do. Three things in particular start to matter:
- Approvals become real. With more requests, "ask your manager" needs to become a clear, recorded yes or no, not an email someone forgets to action.
- Clashes get expensive. At this size two or three people off in the same small team can leave you without cover, and spotting that by eye on a spreadsheet is unreliable.
- Part-timers and balances add up. More people means more pro-rata allowances, more carry-forward, and more chances for a formula to slip.
The must-haves at this size
For a team under 20, look for a planner that covers all of these:
- Self-service requests and one-click approvals, by email and ideally in Slack or Teams.
- A maximum-absent limit so the tool flags or blocks a date once enough people are already off.
- Blocked or blackout dates for your busy periods.
- Pro-rata allowances for part-timers, with days remaining counted automatically.
- UK bank holidays loaded automatically for the right nation, never deducted.
- A shared calendar and wallchart so every manager sees who is off without asking.
The single biggest reason teams of this size move off a spreadsheet is to stop double-booked weeks. A maximum-absent limit turns that from a manual check into an automatic rule.
Why Book Time Off fits
Book Time Off was built for UK teams of roughly this size. It covers the must-haves above in one flat plan:
- One-click approvals by email, plus request and approval DMs in Slack and Microsoft Teams.
- Departments with a manager and a maximum-absent limit, plus blocked dates, for clash control.
- Custom allowances per person, including pro-rata figures for part-timers, with days remaining at a glance.
- UK bank holidays from the GOV.UK feed, half-day bookings, group bookings and carry-forward with optional expiry.
- A calendar and wallchart, plus admin reports with CSV export, all in the same £1 plan.
If you are weighing it against the established names at this size, see Book Time Off vs Timetastic and the best annual leave tracker ranking.
Set a maximum-absent limit, approve requests in one click, and see your whole team's leave at a glance. 30 days free, no card required.
What it costs
A flat £1 per user / month, no minimum, no contract:
| Team size | Per month | Per year |
|---|---|---|
| 12 people | £12 | £144 |
| 15 people | £15 | £180 |
| 19 people | £19 | £228 |
Best for and not best for
✓ Best for
- UK teams of roughly 10 to 20 people
- Anyone past the point a spreadsheet can cope
- Teams that need clash control and real approvals
- Mixed full-time and part-time staff
Look elsewhere if you need
- A separate counted-down balance for every leave type
- Per-person working-day patterns (the week is company-wide)
- Full HR: documents, onboarding, performance, payroll
- A public API for two-way integration
Frequently asked questions
At this size you need real approvals, clash control and accurate balances, which a spreadsheet struggles to provide. A dedicated tracker is the right tool, and our pick is Book Time Off at a flat £1 per user per month: self-service requests, one-click approvals, a maximum-absent limit so too many people cannot be off at once, automatic UK bank holidays and a shared calendar. Timetastic and Leave Dates are the other strong dedicated options.
With 10 to 20 people, several need to request, approve and edit leave at once, so versions clash and changes get lost. There is no real approval step, no alert when two people book the same week, and the remaining-days maths is easy to break. Add part-timers and manual bank holidays and the file becomes a job in itself. Dedicated software removes all of that for a few pounds per person a month.
Use a tool with a capacity limit. In Book Time Off you set a maximum-absent limit per department, so once that many people are off on a date, further requests are flagged or blocked. You can also set blocked or blackout dates for busy periods. That turns clash control from a manual check into an automatic rule, which matters most as a team grows past 10.
You set each part-timer's allowance as a pro-rated number of days, and the planner counts their remaining days against it automatically. Book Time Off loads UK bank holidays from the GOV.UK feed for the right nation and never deducts them from allowance. It uses a company-wide working week rather than per-person working-day patterns, so set part-time allowances as a pro-rated total.
Dedicated trackers are inexpensive at this size. Book Time Off is a flat £1 per user per month with no minimum, so a team of 20 is £20 a month, or £240 a year, with a 30-day free trial and no card. That includes approvals, clash control, UK bank holidays, Slack and Teams, and reporting, features some rivals reserve for a pricier tier.