Most independent optical practices know roughly what proportion of their work is NHS and what proportion is private. Very few can tell you what each is contributing to overall profitability, or how the mix is moving over time.
That's a problem, because the NHS versus private mix is one of the most important financial levers in an independent practice. It affects margin, working capital, and the kind of growth the business can actually pursue.
This article covers what the mix really means financially, why most practices don't track it well, and what good looks like.
NHS and private revenue come from fundamentally different commercial structures.
NHS work is funded at fixed rates set by the General Ophthalmic Services contract. The fees haven't kept pace with inflation in recent years. Voucher values for spectacles are also limited. The result is that NHS work generates revenue but the margin per pair of glasses is comparatively thin once you account for the time of qualified optometrists, the dispensing time, frame and lens costs, and overheads.
Private work is priced by the practice. Private patients can choose higher-end frames, premium lenses, additional coatings, and lens designs that don't fit within NHS parameters. The margin per pair of glasses on a £400 private prescription with premium lenses can be three to four times the margin on an NHS-funded equivalent.
This isn't a criticism of NHS work. NHS revenue provides stable, predictable footfall and a base load of business that keeps the practice operationally efficient. What it does mean is that growing total revenue through NHS work generates significantly less profit per pound than growing through private work.
A practice doing 70% NHS and 30% private has fundamentally different economics from a practice doing 30% NHS and 70% private, even if their total revenue is identical.
The 30% NHS practice will have higher overall margins, more cash generation per appointment, more flexibility to invest in equipment or premises, and a better ability to absorb cost increases like staff wage growth or rent rises.
The 70% NHS practice will have lower overall margins and will be more vulnerable to changes in NHS fee structures or to small increases in cost.
Both can be successful businesses. But the strategic decisions facing each are different, and that difference shows up in the numbers when you look at them properly.
Most independent practices have a rough sense of their NHS versus private split. They know it's “about 60/40” or “around two-thirds NHS.” They don't usually have it broken down formally in their management accounts.
Even fewer track how it's moving over time. The mix can drift slowly without anyone noticing. A new clinician with different conversion habits. A change in patient demographics. A shift in marketing emphasis. Any of these can change the mix gradually, and by the time the impact shows up in overall profitability, you've lost a year of data on what was driving the change.
Even fewer still track the gross margin of each type of work separately. Knowing your overall margin is useful. Knowing that your NHS work runs at 25% gross margin and your private work at 55% gross margin is far more useful, because it tells you which lever to pull when you want to improve overall profitability.
A practice that's properly tracking this will have monthly management accounts that show:
The split of revenue by source. NHS, private prescription, contact lenses, repairs, sundries.
The gross margin for each category, with cost of goods properly allocated by category rather than averaged across the whole practice.
The trend in mix and margin over the trailing twelve months, so you can see the direction of travel rather than just the snapshot.
The conversion data underneath the revenue. Of the patients who came in for an NHS-funded eye test, what proportion went on to a private prescription. This is one of the most actionable numbers in the practice and most practices don't track it.
Once you can see the mix and its margin contribution, several strategic decisions become clearer.
Pricing decisions. If your private margin is much higher than your NHS margin, your private pricing has more room to absorb a price increase without losing customers. If your private margin is closer to NHS margin, you've got a problem with private pricing that needs attention.
Marketing decisions. If you're trying to grow profitability, marketing private work moves the dial more than marketing NHS work, because every additional private appointment generates more profit. Most practice marketing doesn't differentiate.
Clinician decisions. If one optometrist converts NHS appointments to private prescriptions at a higher rate than another, that has real financial value. Knowing it lets you have constructive conversations about technique, recommendations, and the patient journey. There's more on the economics of clinician time in the clinician costs article.
Investment decisions. If you're considering investing in premium frame ranges or additional clinical kit, the question of whether the investment will pay back depends on whether your patient base can support it commercially. The mix data tells you.
This sits alongside the VAT partial exemption issue covered in the VAT apportionment article. The way you split revenue for VAT purposes interacts with the NHS and private split. Practices that get one of these right and the other wrong typically leave money on the table.
If you don't currently see your NHS versus private revenue split with proper margin attribution in your monthly accounts, that's the gap. The data exists in your practice management system and your sales records. It's a question of pulling it together into a report that helps you run the business.
Have a look at the opticians page for more on how I work with independent optical practices, or drop me a message if you'd like to talk about what better financial reporting could look like for yours.
There's no hard sell here, just a conversation about where you are now and whether I can help.
Let's talkOr call 07899 296 552 · leigh.cooke@virtufin.co.uk