The Hidden Revenue in Your Old EICR Certificates
Every EICR you've issued in the last five years is a renewal job waiting to happen. Here's how to estimate what your back catalogue is actually worth — and how to recover it.
Every electrician carrying out EICR work for landlords is sitting on a back catalogue of guaranteed renewal revenue and, in most cases, has no idea how big it is.
Each certificate you issued three or four years ago is approaching renewal. Each renewal is a near-certain booking if the landlord remembers you and you reach out at the right time. Across a typical sole trader's portfolio, the value of that back catalogue is significantly higher than most electricians estimate — and the proportion they actually capture, without a tracking system, is significantly lower.
This post is the maths. A practical framework for estimating what your old certificates are worth, what percentage you're currently recovering, and what changes when you put a system in place.
The Basic Calculation
Three numbers determine the size of your hidden renewal revenue:
- The number of EICR jobs you've carried out in the last five years
- Your average renewal value per job
- Your current recovery rate (the percentage of those jobs you'll actually re-book when they come due)
The first two are easy to find — your invoicing software has the data. The third is the variable that most electricians underestimate, often by a wide margin.
A worked example for a sole trader:
| EICRs carried out in the last 5 years | 30 |
| Average renewal value | £250 |
| Estimated 5-year renewal revenue | £7,500 |
That's just the EICR. Add the typical follow-on work — small remedials, "while you're here" jobs, optional PAT testing add-ons — and the total value of the back catalogue often sits closer to £10,000 to £12,000 over the renewal cycle.
That's the ceiling. The question is what percentage of it you actually recover.
Recovery Rates Without a System
Industry pattern, drawn from electricians who've moved from no system to a tracking system and measured the difference:
- Without any tracking: roughly 40% to 55% of past EICRs convert to renewals. The recovered share is mostly landlords who happen to remember you and reach out first; the rest is lost to forgotten certificates, lapsed timing, or competitors who got in touch when you didn't.
- With a passive tracker (spreadsheet, manual reminders): roughly 55% to 70%. The improvement comes from no longer losing certificates that were never logged, plus a modest lift from any reminders you send when you remember to.
- With an automated reminder cadence: roughly 75% to 90%. The remaining gap is landlords who've genuinely moved on, sold the property, or aren't recoverable for unrelated reasons.
Apply those ranges to the worked example:
| EICR revenue | Lost vs ceiling | |
|---|---|---|
| No system (40-55% recovery) | £3,000 - £4,125 | £3,375 - £4,500 |
| Spreadsheet (55-70% recovery) | £4,125 - £5,250 | £2,250 - £3,375 |
| Automated cadence (75-90%) | £5,625 - £6,750 | £750 - £1,875 |
The gap between "no system" and "automated" is the hidden revenue. For a thirty-certificate portfolio, that's somewhere between £2,500 and £4,000 of recoverable EICR work over a five-year cycle — roughly £500 to £800 a year, before you count the follow-on revenue from each renewal visit.
For a forty- or fifty-certificate portfolio, the hidden revenue is proportionally larger and typically lands above £1,500 a year.
Calculate Yours
Here's the framework. You can run this in five minutes with your invoicing software open.
Step 1 — Count your EICRs. Pull a report of jobs from the last five years filtered for EICR work (or whatever line-item description you use). You're looking for the total number of certificates issued.
Step 2 — Estimate your average renewal value. Take the total EICR revenue from those jobs and divide by the number of certificates. That's your average. Note that renewal jobs sometimes price slightly differently from new inspections — usually a touch lower because the property is a known quantity, sometimes higher if you're charging for newer regulation requirements.
Step 3 — Multiply. Number of certificates × average renewal value = your back catalogue ceiling.
Step 4 — Apply your current recovery rate.
If you don't have a tracking system, assume 40% to 55%. The honest answer is usually closer to the lower end.
If you have a spreadsheet you check most months, assume 55% to 70%. If you check it sporadically, lower.
If you're already running an automated reminder cadence, your recovery rate is what your system reports — and you're not the audience for this post.
Step 5 — Calculate the gap. Ceiling minus current recovery is the hidden revenue sitting in your back catalogue. That's the work that's already yours to lose if you don't act on it.
Why the Numbers Are Bigger Than They Look
Two things usually surprise electricians when they first run this calculation.
Most underestimate the certificate count. The instinct is to remember the bigger jobs and forget the small ones — but EICR work is mostly small jobs at scale, and the sheer volume over five years is usually higher than memory suggests. Pulling the actual figure from invoicing software reveals a portfolio that's 30% to 50% bigger than the back-of-envelope estimate.
Most underestimate the recovery gap. The intuition is "I'm pretty good at staying in touch with my landlords, so I'll recover most of them." The data, when measured, says otherwise. Without a system, recovery rates rarely exceed 55% — and the missing 45% is invisible because you don't know which landlords you've lost or when.
The combination of underestimating both numbers means most electricians think their hidden revenue is somewhere around £500 to £1,000 over five years, when the actual figure is often three to four times that.
What "Hidden" Actually Means
The revenue isn't hidden in a metaphorical sense. It's hidden in a literal one — it's revenue you can't see because you don't know which certificates you've forgotten about.
That's the asymmetry. The certificates you do recover are visible: they show up as renewal bookings on your calendar. The ones you lose are silent. The landlord doesn't email you to say "I let my certificate lapse," and you don't think about them again until you happen to remember the original job five or six years later — by which point they've either renewed with someone else or stopped renting the property altogether.
The way to make hidden revenue visible is to build a complete inventory of every certificate you've ever issued, calculate the renewal date for each, and then have a system that surfaces those dates without you having to remember them. The first part is an audit exercise; the second is a tooling decision.
The Audit Step
If you're convinced enough by the maths to act on it, the first thing to do is build the inventory.
Pull the last five years of invoices, filter for EICR jobs, and capture five fields per certificate: property address, landlord name, landlord email, inspection date, and calculated expiry (typically inspection date plus five years). Drop those into a spreadsheet — the free EICR expiry tracker template gives you a ready-made format.
That single afternoon's work reveals two things. First, exactly how many certificates you've issued — usually a higher number than you'd have guessed. Second, exactly how many of them are coming up for renewal in the next eighteen months, which is the immediate revenue opportunity sitting in your back catalogue right now.
For a deeper walkthrough of the audit and how to turn the spreadsheet into an active pipeline, see the post on building a renewal pipeline from old certificates.
Why Acting Now Compounds
The hidden revenue calculation is a snapshot. Every month you wait, two things happen:
Some certificates lapse. Each month, certificates from your back catalogue cross their expiry date. Once expired, the renewal becomes harder to recover — the landlord either books reactively with whoever calls them first, or lets the property run without a valid certificate until something forces it (a tenant complaint, an insurance claim, a sale).
Your recovery rate decays. Time-since-last-contact is a strong predictor of recovery. A landlord you carried out work for two years ago is a much warmer lead than the same landlord at four years out. Reaching out earlier in the cycle, when memory of you is still fresh, has measurably higher conversion than reaching out at the wire.
For both reasons, the value of the back catalogue is highest when you act on it now, and degrades month-on-month if you don't.
Recovering It
Once you have the inventory, the recovery system has to do three things: capture every new certificate without you having to remember to log it, surface upcoming expiries on its own (without you having to check), and run a multi-touchpoint reminder cadence at no extra human cost.
You can build that yourself with a CRM, calendar, and email automation. Or use Recurvia, which is the same system pre-built specifically for EICR renewals — import your spreadsheet, switch the reminders on, and the platform handles the cadence in your name. The free plan covers the first five reminder sends; if your portfolio is larger, Lite or Pro plans unlock unlimited reminders.
For a typical sole trader with thirty active certificates, one recovered renewal at £250 covers more than a year of the Pro subscription. Everything beyond that is hidden revenue you weren't going to capture without a system.