How to keep track of annual boiler services
Last updated: 6 October 2026
What should you record for each boiler?
| Field | Why you need it |
|---|---|
| Customer name | So you can address the reminder personally |
| Mobile number | To send the reminder |
| Address | The boiler belongs to a property, and some customers have more than one |
| Boiler make and model | Useful for the visit and for the reminder wording |
| Date of last service | The starting point for the next date |
| Next service due | The date everything else depends on |
| Notes | Access, parking, tenant details, anything you will want next year |
| Reminder sent / booked | So you can see who still needs chasing |
A simple spreadsheet setup
Create one row per boiler with the columns above. In Excel or Google Sheets, you can work out the next due date automatically with =EDATE(last_service_cell, 12), which adds 12 months to the last service date. Then sort or filter by next due date each week, and contact anyone due in the next four to six weeks.
This works well for a small customer list. Its weak points are that it relies on you opening it, it does not send anything for you, and it is awkward to use on the move.
What are the alternatives?
- Paper diary or calendar alerts: low cost, but easy to miss, and it is hard to see everything due in a given month.
- A reminder app: tracks every boiler and its due date, shows what is due soon or overdue, and sends the reminder for you. This is what Boiler Service Reminder does.
- All-in-one software: includes certificates, invoicing and scheduling as well as reminders, usually at a higher price. See our comparison of boiler service reminder software.
When should you move on from a spreadsheet?
Consider moving when you notice services slipping through, when checking the sheet each week is a chore, or when you want reminders to go out without you doing anything.
Keep customer data safe
A list of customer names, numbers and addresses is personal data. Keep the spreadsheet password-protected and backed up, and do not share it casually. If you text customers from it, follow the rules in our guide to texting customers.