One of the hardest lessons a dental practice owner learns is that profit and cash are not the same thing. A practice can show a healthy profit in its accounts and still run short of money in the bank, because the largest outflows, the tax bill, the payments on account, and any NHS clawback, are lumpy and arrive long after the income that produced them. Add loan capital repayments, which drain cash without reducing profit, and an owner who draws freely from a healthy-looking account, and even a genuinely profitable practice can hit a cash crunch that feels inexplicable.
This guide is about preventing that. We explain how to build a tax reserve as a sole trader or a company, how to avoid the director's-loan trap that catches owners who over-draw, why NHS clawback is a cash-flow event as much as a contractual one, and how to run a simple reserving and forecasting system that keeps the practice solvent through the lumpy outflows. The theme throughout is the same: treat the big future outflows as money that is already spoken for, not as cash you happen to have, and the crises disappear.
Why dental practices struggle with cash flow
Dental practices have a particular cash-flow profile that makes them prone to the profit-rich, cash-poor trap. Income is reasonably steady, especially with an NHS contract paying monthly, but the outflows are uneven and back-loaded. Tax on this year's profit is largely paid next year. Payments on account front-load tax for the self-employed. Loan capital repayments use cash that never appears as a cost in the profit figure. NHS clawback can recover money already received and spent. And owners, seeing a comfortable bank balance, draw against it. The result is a practice that looks prosperous in its accounts but periodically scrambles for cash when several of these outflows coincide. Recognising the pattern is the first step to managing it.
The two big lumpy outflows: tax and clawback
Two outflows dominate the cash-flow risk for an NHS-involved practice. The first is tax, in all its forms: income tax and National Insurance or corporation tax, payments on account, and the personal tax on extraction for a company owner. These are large, periodic and arrive after the income, so they have to be reserved for in advance. The second is NHS clawback, which recovers the overpayment where delivery falls below 96% of target, often when the money has long since been spent. Both share a dangerous feature: the cash leaves the practice well after the activity that generated the liability, which is exactly the gap that catches an owner who has treated all the cash as available. Reserve for both, and the two biggest cash risks are neutralised.
Why reserving beats reacting
It is worth being clear about why a reserving discipline is so much more effective than dealing with each outflow as it arrives. A practice that reacts, scrambling to find cash when a tax bill or clawback lands, is permanently on the back foot: it pays late and incurs interest, it borrows in a hurry on poor terms, or it raids money meant for something else. A practice that reserves in advance simply pays each outflow from money already set aside, with no scramble, no penalty interest and no emergency borrowing. The same total amount leaves the practice either way, but the experience and the cost are completely different. Reserving converts the lumpy, stressful, sometimes expensive reality of large periodic outflows into a series of routine payments from a pot that was always going to be spent. The discipline costs nothing except the habit of treating the reserve as untouchable, and it removes almost the entire downside, the penalties, the panic and the poor decisions made under pressure, that catches practices which manage cash by reaction rather than by reserve.
Building a tax reserve: sole trader
For a sole trader, the reserving discipline is simple and reliable. Open a separate savings account used only for tax, and move a fixed proportion of every payment you receive into it as the income arrives, before it can be absorbed into spending. Size the proportion to cover income tax and Class 4 National Insurance, plus the payments on account that front-load your bill, so a third or more is a sensible starting point for a higher earner. Lift the proportion as your profit climbs into the higher bands, where the marginal rate is around 42%. Then, at each January and July deadline, the money is already sitting there. Our guide to payments on account for dentists explains the front-loading the reserve has to cover. The owners who never have a tax crisis are simply those who treated the reserve as never being theirs to spend.
Building a tax reserve: company
A company owner has two layers of tax to reserve for, and it is worth keeping them separate. First, corporation tax on the company's profit, which the company must hold cash to pay after its year-end. Second, the personal tax on whatever the owner extracts as salary or dividends, which the owner must reserve for in their own Self Assessment. A common mistake is to reserve for one and forget the other, leaving either the company short when its corporation tax falls due or the owner short at their personal deadline. Coordinating the two, and timing dividend declarations against both the company's distributable profit and the owner's personal tax position, is more complex than a sole trader's reserve, which is one reason a company benefits from closer accountant involvement. Our guide to strategic financial planning for a practice covers the coordination.
The director's-loan trap from over-drawing
For company owners there is a specific cash-flow trap worth naming. If you draw more cash from the company than there is profit available to cover as salary or dividend, your director's loan account becomes overdrawn, and an overdrawn director's loan account triggers a tax charge on the company, broadly at the dividend upper rate on the balance outstanding nine months and a day after the year-end. A loan over £10,000 can also create a benefit-in-kind charge. So using the company's cash to solve a personal cash-flow problem can create a fresh tax problem on top of it. The discipline is to draw within the profit available, declare dividends properly against distributable reserves, and never treat the company account as a personal overdraft. Reserving correctly removes the temptation to over-draw in the first place, because the cash you see is genuinely yours to take.
NHS clawback as a cash-flow event
It is worth treating clawback explicitly as a cash-flow matter, not just an accounting one. The NHS contract pays smooth monthly amounts regardless of delivery, so if you under-deliver you have been paid ahead of what you earned, and the year-end reconciliation recovers the overpayment below 96% delivery. That recovery is a real cash outflow, often landing when the money is gone. The protection is twofold: treat the monthly NHS payment as partly advanced rather than fully earned when delivery is behind, and reserve against a likely clawback just as you reserve for tax. Our guide to working capital and overdraft options covers the facilities that can bridge a clawback if one does arrive unexpectedly, but reserving for it in advance is far better than borrowing to cover it after the fact.
The hidden drain: loan capital repayments
One outflow deserves special attention because it is invisible in the profit figure: loan capital repayments. When you repay the capital portion of a practice or equipment loan, cash leaves the business, but that repayment is not a deductible expense and does not reduce your profit, because repaying borrowed money is a capital transaction rather than a cost. The interest portion is deductible; the capital portion is not. The consequence catches many owners out: you can have a healthy taxable profit, pay tax on it in full, and still find the cash gone, because a large slice of it went to repay loan capital out of post-tax money. A practice with significant borrowing therefore needs more cash than its profit suggests, because it must fund both its tax and its capital repayments from the same earnings. Building the capital repayments explicitly into your cash forecast, separately from the interest, is what stops this hidden drain from causing a surprise shortfall.
Why timing, not profitability, causes most crises
It is worth stating clearly that most dental cash-flow crises are timing problems, not profitability problems, because the two call for completely different responses. A timing problem is a profitable practice that runs short because outflows bunch up, several tax dates, a clawback, a quiet month and a capital repayment coinciding. The cure is reserving and forecasting, so the cash is there when the bunched outflows fall due. A profitability problem is a practice that runs short because it genuinely spends more than it earns, and no amount of reserving or borrowing fixes that; the cure is in the cost base or the income. Misdiagnosing one as the other is dangerous: treating a profitability problem with an overdraft just delays the reckoning, while treating a timing problem as a profitability crisis can prompt unnecessary cuts. The first question in any cash squeeze is therefore which kind it is, and the rolling cash forecast, set against the profit figure, is what answers it.
Seasonality and the appointment book
Dental income is not perfectly even across the year. Holiday periods, school terms and local patterns create quieter months where income dips while fixed costs, staff, premises, loan repayments, carry on unchanged. A practice that budgets on its average month is repeatedly caught out by the quiet ones. The answer is to plan cash around the realistic low months, not the average, holding enough buffer to cover the predictable seasonal dips without strain. Knowing your own seasonal pattern, from your management accounts, lets you anticipate the quiet periods and reserve accordingly, rather than treating each one as a fresh surprise.
The psychology of the healthy-looking balance
Much of cash-flow trouble is psychological, and naming the trap helps avoid it. The danger is the healthy-looking bank balance: an account that shows a comfortable figure, most of which is in fact already spoken for by tax not yet paid, a clawback not yet recovered, and loan capital not yet repaid. Seeing the comfortable number, an owner draws against it, spends on the practice, or relaxes their guard, only to be caught when the spoken-for outflows fall due. The mental discipline that prevents this is to think not in terms of the balance but in terms of free cash: the money genuinely available after every reserve and known outflow is set aside. A practice that keeps its tax and clawback reserves in separate accounts makes this concrete, because the main account then shows something much closer to genuinely free cash. The single most useful habit an owner can build is to stop looking at the headline balance and start looking at what is truly free after the reserves, because the gap between the two is exactly where cash-flow crises live.
A simple reserving system
The system that works is unglamorous and consistent. Keep a separate reserve account for tax and, ideally, a separate cushion for a possible clawback. Move a fixed proportion of every receipt into the reserve on the day it arrives, not at month-end. Treat the reserve as untouchable for anything but its purpose. Review the proportion periodically with your accountant as profit changes. And never let drawings or company extraction exceed what is genuinely available after the reserves are set aside. This handful of habits, applied without exception, prevents almost every dental cash-flow crisis, because it converts the lumpy future outflows into money that is already put by when they fall due.
A worked example
Take a company with £200,000 of profit and an NHS-involved practice.
- Corporation tax reserve. The company holds cash to meet its corporation tax on the £200,000, due after the year-end. This is reserved at company level and not treated as available for extraction.
- Personal tax reserve. The owner reserves separately for the personal tax on the salary and dividends they extract, ready for their Self Assessment deadlines.
- Clawback reserve. If delivery is tracking below target, the company holds a cushion against a likely year-end clawback rather than spending the full monthly NHS payments.
- The over-drawing risk. If the owner draws more than the available profit supports, the director's loan account goes overdrawn and a tax charge follows. Reserving correctly keeps drawings within the safe limit and avoids the charge.
Manage these four together and a £200,000-profit company has comfortable, predictable cash flow. Ignore them and the same profitable company can lurch from one outflow to the next, borrowing to cover liabilities it should have reserved for.
Practical tips for staying ahead of the outflows
A few practical habits make the difference between a practice that manages cash well and one that lurches. Diarise every known outflow date, the January and July tax dates, the corporation tax due date, the year-end reconciliation, well in advance, so none arrives unannounced. Automate the reserve transfer where you can, so a fixed proportion of income moves to the reserve account without relying on memory. Reconcile monthly, so your view of the cash position is always current rather than a guess. Build the loan capital repayments and any clawback into the forecast explicitly, because these are the outflows most often forgotten. And review drawings against the forecast before taking money out, rather than after. None of these is complicated, but applied together and consistently they convert cash management from a recurring source of stress into a routine that runs in the background, leaving the owner free to focus on the practice itself rather than on whether there will be enough in the account when the next big outflow falls due.
Forecasting cash twelve months out
The tool that ties it all together is a rolling cash forecast looking at least twelve months ahead, because the big tax and clawback outflows can be more than a year from the income that caused them. Map expected income, fixed and variable costs, loan repayments, every tax payment date and any anticipated clawback, and update it monthly. The forecast shows the pinch points, the months where several outflows coincide, while there is still time to prepare for them. This is the single most valuable financial habit an owner can maintain, because it turns the lumpy, back-loaded outflows that catch unprepared practices into scheduled events you have already funded. Paired with the right monthly KPIs, which our guide to the financial KPIs every owner should track sets out, a forward cash forecast keeps a profitable practice not just profitable but solvent, which are emphatically not the same achievement.
Coordinating extraction with cash flow in a company
For a company owner, the timing of extraction, how and when you take salary and dividends, is itself a cash-flow lever worth using deliberately. Dividends can only be declared from distributable profits, and taking them in a controlled, planned way, rather than drawing cash ad hoc, keeps the director's loan account healthy and the personal tax predictable. A sensible rhythm is to set a regular salary, review distributable profit periodically, and declare dividends in line with both the available profit and your reserved personal tax, rather than dipping into the company account whenever cash is needed. This discipline does double duty: it manages the company's cash so it can meet corporation tax and any clawback, and it manages your personal extraction so you neither over-draw into a director's-loan charge nor under-draw and leave money trapped. Our guide to strategic financial planning develops the coordination of extraction, tax and cash flow that a company owner has to manage as one system.
Working-capital buffers
Finally, hold a sensible working-capital buffer: a cushion of accessible cash, or an agreed facility, that absorbs the normal timing differences between income and outflows. A buffer covering a few months of fixed costs is a common aim, scaled to how variable your income is and how lumpy your outflows are. The crucial rule is that the buffer is for timing, not for funding losses. If you find yourself drawing on it to cover ongoing shortfalls rather than timing gaps, that is a profitability problem to address at source, covered in our guide to managing overhead costs, not a cash-flow problem to paper over. A well-run practice reserves for its tax, provides for its clawback, forecasts its cash a year ahead and holds a modest buffer for timing, and with those four in place, the gap between looking profitable and being solvent simply closes.