Running the firm, 29 October 2026
Scheduling engineers without double-booking: diary options for small firms
For two to ten engineers, a shared online calendar with one person allowed to book stops most double-booking for little or nothing. Job management software adds job sheets, reminders and invoicing for roughly £25 to £270 a month. A paper diary works only while the person holding it is always reachable. The tool matters less than one owner and fixed booking rules.
Why do small firms double-book?
Because the diary lives in more than one place. The owner books from his phone on site, the office books from the desk diary, and an engineer agrees a return visit with the customer at the door. Each is right on its own. Together they clash.
I'm doing it all on pen and paper.
Paper isn't the problem in itself. The problem is that only one person can see it, so every booking has to go through them, at any hour. A gas firm we spoke to, run by an owner and his wife with three engineers, described the same pressure from the other side: "It's more when we're not here, that's the issue."
What are the options?
Four, in rising order of cost and capability.
| Option | Cost (as of October 2026) | Who it suits | Watch out for |
|---|---|---|---|
| Paper diary or wall planner | A few pounds | One office, owner nearly always there | Nobody else can see or book it |
| Shared Google Calendar | Free with Google accounts; Workspace adds business email | 2 to 5 engineers, owner or one admin booking | No job sheets, parts or invoicing |
| Shared Outlook calendar (Microsoft 365 Business Basic) | £4.20 per user per month on an annual plan without Teams, £5.40 with Teams | Firms already on Outlook email | Same limits as Google |
| Job management software | ServiceM8 £25 to £269 a month by job volume; Fergus and Tradify per-user plans, see their pricing pages | 3+ engineers wanting jobs, certificates, reminders and invoices linked | Contracts, set-up time, getting engineers to use the app |
Prices change and are often shown before VAT, so check the vendor's page. Microsoft's Business Basic price comes from its UK page and excludes VAT. ServiceM8 prices its UK plans by jobs a month with unlimited users: Starter £25 for 50 jobs, Growing £59 for 150, Premium £119 for 500 and Premium Plus £269 for 1,500. Fergus lists Essentials and Professional plans with monthly billing and "no lock-in contracts", currently on a time-limited discount. Tradify's pricing page showed per-user prices in US dollars when we checked, with scheduling and Google Calendar sync on every plan.
What does each option cost a four-engineer firm in a year?
Here's a firm with four engineers and the owner, doing about 120 jobs a month, worked out with prices checked on vendor pages in October 2026, before VAT.
Yearly diary cost for four engineers plus the owner, 120 jobs a month
Five people need to see the diary. Prices before VAT, as of October 2026.
| Paper diary and wall plannerabout £30 | £30 |
| Google Calendar on free accounts£0 | £0 |
| Microsoft 365 Business Basic, annual, no Teams5 users × £4.20 × 12 months | £252 |
| ServiceM8 Growing (150 jobs a month, unlimited users)£59 × 12 months | £708 |
| Gap between a shared calendar and job software£708 − £252 | £456 |
The software premium in this example is £456 a year, about £38 a month. That's worth paying if it saves the office a couple of hours a week of retyping job sheets into invoices. It's not worth paying if nobody fills in the job sheets.
Which option should you pick?
Pick the cheapest one that everyone who books can see, and that your engineers will open. Use the quick check.
If you're the only one who books and you always have it with you, paper is fine. Photograph each week's page so it's backed up.
One calendar per engineer in Google or Outlook, shared with everyone who books. Cheap, quick to set up, and engineers see it on their phones.
Run a 14-day trial with two engineers on real jobs before signing. Compare at least two; see best job management software.
The risk on the software side is paying a monthly bill for what ends up as a smart diary. If you'll only use the diary, a calendar does that for less.
How do you set up a shared calendar properly?
Make one calendar per engineer, give each a colour, and share them so the person who books can make changes and the engineers can see event details.
Google Calendar has five sharing levels: see only free/busy, see event details, make changes (with private events shown only as busy), make changes and see event details, and make changes and manage sharing. Give "make changes" to whoever books and "see event details" to engineers. Keep "manage sharing" to the owner.
- One calendar per engineer.
Name it after them, for example "Dan van 2".
- Share with the booker.
Give make-changes rights to the one or two people allowed to book.
- Share with the engineer.
View-only on everyone else's, edit on their own if they log their own return visits.
- Use a fixed event title.
"Postcode, customer surname, job type", for example "SN2 4, Patel, boiler service".
- Put the address and phone number in the location and notes.
Engineers tap it for directions.
- Block travel time.
Add 30 minutes between jobs as a separate event, or longer for rural work.
What booking rules stop double-booking?
Rules beat software. Agree these with the team and write them on one page.
The rest rule matters for firms that run emergency call-outs. Workers are normally entitled to 11 hours' rest between working days and a 20-minute break if they work more than six hours, so a 10pm call-out and a 7am start the next day doesn't work.
Where Nexley fits
Nexley is the AI back office for UK trade firms: five AI assistants run your tenders, quotes, buying, scheduling and invoicing. It connects to the tools you already work in, you run it all from WhatsApp, and you approve everything. £799 a month.
For scheduling, Nexley keeps your engineers' diaries in a shared calendar, books jobs from enquiries you approve on WhatsApp, flags clashes and travel gaps, and messages engineers their next day's jobs with addresses. You confirm each booking, and engineers keep the calendar app they already use.
Common questions
Is Google Calendar good enough to schedule engineers?
For two to five engineers with one person booking, usually yes. It's free, works on every phone and lets you control who can change what. You'll need something else for job sheets, certificates and invoicing.
How many engineers before I need job software?
There's no fixed number. The trigger is when retyping job details into certificates and invoices takes hours a week, or when bookings go wrong because the office can't see what engineers did.
Should engineers book their own return visits?
Only into their own calendar and only if the office can see it. Otherwise they tell the customer the office will confirm, and the office books it the same day.
How do I schedule subcontractors?
Give each regular subcontractor a calendar you control and share it view-only with them, or send the week's bookings as a message every Friday. Don't give subcontractors edit rights to your engineers' calendars.
Sources
- Google Calendar Help: Choose what others can do with your calendar
- Microsoft: Microsoft 365 Business Basic (UK)
- ServiceM8: UK pricing
- Fergus: UK pricing
- Tradify: pricing and plans
- GOV.UK: Rest breaks at work
Every rule, rate and date above was checked against these sources on the date shown at the top.
Topic: Running the firm
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