A tax bill is not a surprise. The cashflow hit usually is. VAT and Corporation Tax rarely hurt because the numbers are wrong; they hurt because the money leaves in one lump, in a month that also holds payroll, rent, a supplier run and a customer who has decided that “30 days” means “when we get round to it”. Plan the payment weeks ahead and you choose from every option, including the cheapest one, doing nothing because the cash is already set aside. Leave it to deadline week and you are choosing between expensive ones.
Two dates, and the trap between them
VAT is due by the deadline shown on your VAT return, and the money must reach HMRC’s account by that date, even when it falls on a weekend or bank holiday (gov.uk). In practice, unless you pay by Faster Payments, that means having it there by the last working day before. Different rules apply if you use the Annual Accounting Scheme or make VAT payments on account.
Corporation Tax is the one that catches people out. For companies with taxable profits up to £1.5 million, the tax is due 9 months and 1 day after the end of the accounting period (gov.uk). The Company Tax Return itself is not due until 12 months after the period ends (gov.uk). Read those together: the payment normally falls due about three months before the return. A company can still be finalising its accounts while the money is already owed. If your planning starts when the accountant sends the final figures, it starts late. (Above £1.5 million of profit the regime changes again, to quarterly instalments.)
Why good years produce bad months
A stable business can plan tax from last year’s numbers. A growing one cannot. Revenue rises, so the VAT bill rises. Profit improves, so Corporation Tax rises. The team grows, so payroll rises with it. The jobs get bigger, so customers take longer to pay, and more cash sits in stock, materials and work in progress. On paper the business is stronger. In the bank it can feel tighter.
That is why tax shocks hit good businesses, not just struggling ones. A £10,000 bill was manageable last year. A £35,000 bill this year can be correct, affordable across a year, and still painful in the one month it has to leave the account. (If slow payers are part of the squeeze, remember the law lets you charge statutory interest and a fixed sum on overdue invoices.)
What lateness costs in 2026
Two meters start running the day a payment is missed.
Interest, from day one. HMRC charges late payment interest from the first day a payment is overdue until it is paid in full, at Bank of England base rate plus 4 percentage points. With base rate held at 3.75% at the June meeting, that is 7.75% now, a rate in force since 9 January 2026 (HMRC, Bank of England).
Penalties, on a ladder. For VAT, pay in full or agree a payment plan within 15 days of the due date and there is no late payment penalty. From day 16, the first penalty is 3% of whatever was outstanding at day 15; if anything is still unpaid at day 30, a further 3% of the day-30 balance is added; and from day 31 a second penalty accrues daily at 10% a year on the outstanding amount, on top of the interest (gov.uk). Those rates were 2%, 2% and 4% until April 2025, so if your mental model says VAT penalties are a slap on the wrist, it is out of date.
The deeper cost is positional. Miss the deadline and the conversation becomes “how do we stop this getting worse”. Ahead of it, the conversation is “which route is cheapest for us”. Same bill, weaker hand.
Time to Pay is a safety net, not a plan
If you genuinely cannot pay, contact HMRC as early as possible, ideally before the deadline (gov.uk). Agreeing a payment plan by day 15 avoids the first VAT penalty, and for VAT there is an online self-serve route for setting one up, paid by Direct Debit.
Be clear about what a Time to Pay arrangement is, though: an arrears solution. HMRC will ask for your tax reference, bank details and a picture of income and spending, and it expects savings and assets to go towards the debt first; for company tax debt it expects the business to consider releasing assets or raising funding before instalments are agreed (gov.uk). Interest at 7.75% keeps running for the life of the plan. Break the conditions and the arrangement can be cancelled, with penalties then charged on what was outstanding as though the protection had never applied.
So the distinction worth writing down is this. If you cannot pay, speak to HMRC early; that is exactly what Time to Pay is for. If you can pay, but paying in one lump would hollow out working capital, that is a different problem, and you have more options before the deadline than after it.
Spreading the bill with short-term finance
One of those options is tax payment finance: short-term borrowing used to pay HMRC in full and on time, repaid monthly over a fixed period. This is an established product category, not an exotic one; the British Business Bank describes VAT loans in exactly these terms, short-term finance to smooth cashflow around quarterly VAT bills (British Business Bank).
The arithmetic is the easy part. A £36,000 VAT bill paid in one go is £36,000 out of the account in a week. Spread over three months, it is £12,000 a month before interest and fees. A £60,000 Corporation Tax bill over six months is £10,000 a month; over twelve, £5,000. The tax is not a penny cheaper, and the facility has a cost on top. What changes is the shape: a lump becomes a schedule the cashflow forecast can absorb without touching wages, supplier terms or booked work.
The strongest cases are timing problems in sound businesses: a bigger-than-planned VAT bill after a strong quarter, a Corporation Tax bill that rose because profit genuinely improved, cash tied up in stock and unpaid invoices, or a seasonal firm with lumpy income and flat tax dates. The wrong cases matter more. If the monthly repayment is not comfortably affordable, if the tax debt is one symptom of a wider solvency problem, or if every quarter needs rescuing, finance is not smoothing timing, it is hiding a broken model, and the fix lives in pricing, margins, collections or drawings. Use finance to smooth timing; never to disguise the model. Before signing anything, run the repayment through our business loan repayment calculator and weigh the all-in cost, fees included, against the alternatives above.
The habit that beats both
The cleanest position needs no lender and no negotiation. It is built from three small disciplines, started before any bill exists.
Treat VAT as money you are holding, not money you have: on a standard-rated £1,200 invoice, £200 is VAT, and moving it to a separate account the day the customer pays makes the quarterly bill a transfer rather than an event. It is the same discipline we recommend sole traders use for income tax. Estimate Corporation Tax monthly from management accounts rather than waiting for year-end precision; a rough figure every month beats an exact panic in month nine. And keep a rolling 13-week cashflow forecast with VAT, PAYE and Corporation Tax dates written on the same page as payroll and rent, then ask one question before dividends, equipment or big supplier commitments: will paying the next tax bill in full make the business weaker next month? If the answer is yes, start comparing options while all of them are still open.
Direct Debit, and where HMRC is heading
VAT can already be paid by Direct Debit: set it up at least 3 working days before submitting the return, and HMRC collects automatically 3 working days after the payment deadline shown on the return (gov.uk). For a firm that has the money ready, this is the cheapest tax-planning tool there is. The deadline meets itself.
It may also be where everything is heading. On 23 June 2026 the government opened a consultation on requiring VAT and PAYE return liabilities to be paid by Direct Debit, with the stated aim of reducing late payment, limiting the flow of tax debt and simplifying payment; it closes on 16 August 2026 (gov.uk). Whether or not the rule lands in that exact form, the signal is unambiguous: HMRC wants tax paid on time, automatically, with fewer businesses drifting into arrears. Planning for the payment is becoming less optional by the year.
Five questions before any facility
- Can we pay HMRC in full without damaging working capital? If yes, pay and move on.
- If not, what is the smallest amount we actually need to spread?
- Is the bill final, estimated, or still moving?
- Does the monthly repayment fit the 13-week forecast comfortably, not heroically?
- Does this solve a timing problem, or postpone a bigger one?
VAT and Corporation Tax bills are predictable, and so is the pressure they create. The mistake is meeting a predictable bill as an emergency, because by deadline week the choices have shrunk to pay in full, ask HMRC for time, or scramble. Set the money aside as you go where you can. Forecast the payment before it lands. And if one large bill would strain an otherwise sound business, spreading it over a few months is a legitimate tool, provided HMRC is paid on time, the repayment fits, and next quarter’s bill is already in the plan. The tax leaves the account either way. Whether it leaves as a crisis or as a line item is the part you control.
