Why a transport company in a loss year keeps paying the provisional corporate income tax assessment every month on last year's profit

At the end of August, the managing director of a transport company with 45 tractor units was looking at his bank statement. That month's diesel bill was almost €60,000 higher than a year earlier. A few lines further down, as every month, was a direct debit of €3,282 from the Dutch Tax Administration: the instalment of the provisional corporate income tax assessment for 2026.

That instalment had been calculated in January on a profit that will not materialise in 2026. The company has been making a loss since May. The director and his accountant both knew that, but the direct debit kept running, because nobody saw it as a decision.

The provisional assessment works from last year's profit, and as long as you report nothing, it keeps doing so while this year the money flows the other way.

We earn our money with cash flow forecasts for businesses like this, so read the conclusions below with that in mind.

What happened to a transport company's costs in 2026

The diesel price at the pump stood at €2.664 per litre on 3 September 2026, a record, and according to the trade journal Transport Online (3 September 2026) the cause lies in the war with Iran that broke out at the end of February and disrupted passage through the Strait of Hormuz. Industry association TLN (fuel developments, September 2026) calculates that diesel has become about 40 percent more expensive since January 2026 and that fuel makes up on average 20 to 25 percent of a transport company's total costs. TLN advises members to agree a joint reference point for the fuel price with their customers and, when prices rise quickly, to switch from monthly to weekly adjustment; anyone without such a reference point in their contracts pays the increase out of their own margin.

On top of that came the HGV toll (vrachtwagenheffing) on 1 July 2026. According to the Rijksoverheid (Dutch central government; government information, 2026), the toll applies on almost all motorways and on a number of provincial and municipal roads. On the same day the Eurovignette for the Netherlands ended and motor vehicle tax for trucks up to 12 tonnes was abolished. From 1 September to 31 December 2026 a temporary discount of 22.3 percent on the rate applies. On its in-depth page about the toll, TLN gives an average rate of 19.1 cents per kilometre at 2026 prices, with 20.1 cents for a Euro 6 tractor unit above 32 tonnes.

ING Research (sector outlook, market report, February 2026) already expected before the toll that the net costs of road haulage would rise by 7 to 8 percent in 2026 and that almost half of customers wanted to negotiate about the toll. In the update that Transport Online summarised on 14 September 2026, ING arrives at a diesel price 30 percent above the level of a year earlier, which alone means 6 percent extra costs, with volume growth of around 1 percent. According to ING, road haulage revenue will rise by around 15 percent this year. That figure measures revenue, largely costs passed on, and ING itself adds that margins are under pressure because hauliers are driving the same volumes at much higher costs.

With transport companies we see that costs are rarely passed on in full. Part of the revenue is in tenders with a fixed rate for the year, part has a diesel clause (fuel surcharge) that follows with a month's lag, and in September the HGV toll is still being negotiated with many customers. The difference between the cost increase and what the customer pays is the 2025 profit that disappears in 2026.

How the provisional assessment works and why it keeps running in a loss year

According to the Dutch Tax Administration (government information, 2026), most private limited companies (bv's) receive a provisional assessment (voorlopige aanslag) for corporate income tax (vennootschapsbelasting, VPB) at the start of the year, a provisional calculation based on data from previous years. You pay it in monthly instalments, and all provisional assessments are settled with the final assessment. You can have the assessment changed yourself via Mijn Belastingdienst Zakelijk or your tax software, and the Dutch Tax Administration processes at most three increases a year. For a reduction, the Dutch Tax Administration sets no maximum.

What the Dutch Tax Administration does not do is check by itself whether this year's profit still resembles last year's. It only has that information once you file the return, and you file the 2026 return in 2027. Until then, the provisional assessment is an estimate that only you can adjust.

If you make a loss, then under the Dutch Tax Administration's rules for loss relief that loss is first offset against the previous year's profit (loss carryback, in the English-language literature tax loss carryback), and what remains is carried forward without time limit against future profits, in full up to €1 million of profit and for half above that. The tax you paid for 2025 therefore comes back. You partly determine the timing yourself: after filing the return for the loss year you can ask in writing for provisional loss relief, under which up to 80 percent of the reported loss is offset in advance, on condition that the assessment for the previous year is final. The rest follows with the final assessment for the loss year.

According to its page on receiving tax interest, the Dutch Tax Administration only pays interest on money you paid through a provisional assessment that was too high if, after 1 July of the following year, it takes more than eight weeks over your request or more than thirteen weeks over your return. Anyone who overpays in September 2026 and files in March 2027 gets the money back without interest. The other way round, the Dutch Tax Administration does charge tax interest if you paid too little: from 1 July after the tax year until six weeks after the date of the assessment. That interest does not apply if you file the return before 1 June and the Dutch Tax Administration adopts it unchanged, or if you request a provisional assessment before 1 May that is issued as requested.

For years that interest was the reason to leave the provisional assessment too high rather than too low. Corporate income tax carried a higher rate than other taxes, 8 percent against 4 percent in the years that were litigated. The Hoge Raad (Dutch Supreme Court; ruling of 16 January 2026, ECLI:NL:HR:2026:59) declared that higher rate non-binding, because there is no good reason to charge a higher interest rate for corporate income tax than for other taxes. The Dutch Tax Administration then aligned the percentages: according to its overview, tax interest on corporate income tax is 7.5 percent for 2024, 6.5 percent for 2025 and 5 percent from 1 January 2026. The price of an estimate that is too low has therefore fallen from 7.5 percent for 2024 to 5 percent now, and you only pay that price if your return comes in after 1 June.

Why a director does not see the direct debit as a decision

In August, the director from the opening had his attention on the diesel bill and on two customers who had not yet accepted the HGV toll in their rates. Sims (Journal of Monetary Economics, 2003, peer reviewed) described rational inattention: anyone who can only process limited information focuses attention on the variables that move most and leaves the stable ones alone. Maćkowiak, Matějka and Wiederholt (Journal of Economic Literature, 2023, peer reviewed) show in their review of twenty years of research that this behaviour keeps recurring in experiments and in company data: people and businesses react slowly to variables that rarely change, even when those variables are worth a lot of money. A direct debit for the same amount every month is the most stable item on the statement and therefore attracts the least attention.

Chetty, Looney and Kroft (American Economic Review, 2009, peer reviewed) showed with an experiment in a supermarket that people react less to a tax that is not on the price tag, even though they do pay it. In a management report, corporate income tax sits below operating profit, as a single line per year, and at the bank it appears as a direct debit without explanation. So the tax is in the report, but it does not come up in any management meeting.

Bethmann, Jacob and Müller (The Accounting Review, 2018, peer reviewed) studied the instrument you do have in a loss year, loss carryback. They found that about a third of more generous refunds of previously paid tax to loss-making companies goes into investment and the rest is held as cash or paid out. At the same time they warn that those investments mainly come from companies prone to risky overinvestment, and that unconditional refunds keep companies going that would have been better off stopping. The Dutch scheme limits carryback to one year, and that makes the timing of your return more important than the size of the amount.

Worked example: a transport company with 45 tractor units

In this worked example a transport company with 45 tractor units and 70 employees has revenue of €9.45 million in 2025, €210,000 per tractor unit. Each tractor unit drives 110,000 kilometres a year at a consumption of 31 litres per 100 kilometres, together 1,534,500 litres of diesel. At an average bulk price of €1.50 per litre excluding VAT, fuel cost €2,301,750 in 2025, 24 percent of revenue, within the 20 to 25 percent TLN mentions. Profit before tax for 2025 was €190,000, 2 percent of revenue, on which the company paid 19 percent corporate income tax: €36,100. In this example 2024 and 2025 were comparable years, so the provisional assessment for 2026 that arrived at the end of January was also €36,100, in eleven instalments of €3,282 from February to December. The 4 percent wage increase ING mentions is covered in this example by the annual rate indexation and otherwise stays outside the calculation.

In 2026 the average bulk price rises to €1.95 per litre, 30 percent higher, the percentage ING mentions in September. At the same volume that is €690,525 of extra fuel. Sixty percent of revenue falls under contracts with a diesel clause that follows the TLN fuel monitor with a month's lag; of that, €414,315 is passed on, and with a price that rises all year the lag costs about one twelfth of that, €34,500. Forty percent of revenue is in tenders with a fixed rate for 2026 without a clause; the company pays that €276,200 itself. The diesel increase therefore costs €310,700 of profit in 2026.

The HGV toll comes on top of that from 1 July. Of the 4,950,000 kilometres a year, the company drives 65 percent on tolled roads, 268,125 kilometres a month. July and August at 20.1 cents is €107,800, September to December at 20.1 cents minus the temporary discount of 22.3 percent is €167,500, together €275,300. The abolished Eurovignette saves €28,700 in the second half of the year, because the annual rate for a Euro VI tractor unit with four or more axles had been €1,274 since 25 March 2025 according to TLN; we leave the reduction in motor vehicle tax out of consideration here. Net, the toll costs €246,600 in 2026. In this example the company passes 70 percent of that on to customers and pays 30 percent itself: €74,000.

In this example the swing from profit to loss is a difference of €384,700, 4 percent of revenue, while the company drives the same number of kilometres. At 1,534,500 litres, every cent per litre you do not pass on is €15,345 a year.

On 15 September 2026 the company has paid eight instalments, February to September: €26,256. Three more instalments of €3,282 are scheduled, €9,846. If the director does nothing, the full €36,100 will have been paid by the end of December on a profit of minus €194,700. In January 2027 the provisional assessment for 2027 arrives, again based on data from previous years, so again around €36,100, with a first instalment in February. Only when the accountant files the 2026 return in May 2027 does the Dutch Tax Administration see the loss. The loss of €194,700 is then offset against the 2025 profit: the €36,100 for 2025 comes back, and €4,700 of loss remains for 2027. With a request for provisional loss relief, 80 percent comes in advance: 19 percent of €155,760 is €29,600, the remaining €6,500 follows with the final assessment for 2026, and that can take a year.

The difference between the two columns rises from €42,700 in March 2027 to €72,300 in May 2027, in the months when the company in the example is just coming out of its winter dip and the bank is looking at the 2026 annual figures. At the 5.1 percent the company in this example pays on its overdraft facility, €78,764 of parked money costs €4,000 of interest a year. That interest is small compared with the €78,764 itself, because 40 percent of the annual loss sits with the Dutch Tax Administration at the moment when credit headroom is tightest.

What is acceptable and when you reach it

A provisional assessment that differs from the actual tax is normal, because it is an estimate. At businesses with a monthly results forecast, we see that a deviation of 20 percent between the provisional assessment and the eventual tax is acceptable and usually only arises in the fourth quarter. A deviation of 100 percent, an assessment on profit while a loss is being made, is a signal that the forecast and the tax position are not talking to each other.

The moment you reach that depends on how quickly you have your figures. In the example the loss was visible in the quarterly figures in May 2026, when the diesel price had been above the reference point of the clauses for three months and the first tenders without a clause started to cost money. That is the moment to adjust the provisional assessment. Anyone who waits for the annual accounts in March 2027 meanwhile pays nine unnecessary instalments of €3,282, €29,538, on a profit that does not exist.

The limit on the other side is tax interest. If you reduce the assessment to zero and 2026 still ends with €50,000 profit thanks to a falling diesel price and a successful negotiation, the tax is €9,500. If you file the return before 1 June 2027 and the Dutch Tax Administration adopts it, you pay no interest on it. If the return comes in the autumn, the 5 percent interest runs from 1 July 2027 until six weeks after the assessment, about €200 for five months. That is the full price of an estimate that is too low, and it is negligible against the €42,700 to €72,300 that an estimate that is too high ties up in spring 2027 in this example.

How to manage the tax cash flow in a loss year

Put corporate income tax as a separate line in the cash flow forecast, with the instalments of the provisional assessment per month and the expected refunds in the month you expect them. In the example, February 2027 then shows an instalment of €3,282 that you only pay if you do not adjust the 2027 assessment, next to a refund of €13,128 that only comes once you have filed your return, and those two lines side by side force a choice. How to maintain such a forecast monthly is set out in the article on rolling forecasts, and why cash behaves differently from the profit and loss account in a bad year, in the article on cash flow as a brake on growth.

Reduce the provisional assessment as soon as the quarterly figures show a loss, via Mijn Belastingdienst Zakelijk or via your accountant. In the example that saves seven instalments, €22,974, in May 2026, and still three instalments, €9,846, on 15 September. A reduction costs nothing and the Dutch Tax Administration sets no maximum for it.

Check the provisional assessment for 2027 in the first week of January. It is based on data from previous years, so in the example on a profit year, and every month you wait costs €3,282. The rates for 2027 are in the 2027 Tax Plan (Belastingplan 2027) presented on 15 September 2026, which still has to pass the House of Representatives and the Senate; calculate with the rates your accountant confirms after it has been debated.

The 2025 return should go out early, and ask your accountant to expedite a final assessment for 2025 where possible. According to the Dutch Tax Administration, provisional loss relief for 2026 is only possible once the assessment for 2025 is final. In the example that is the condition for the €29,600 in spring 2027.

File the 2026 return as early as possible in 2027 and immediately ask in writing for provisional loss relief of 80 percent. Bethmann, Jacob and Müller found that most of such a refund is held as cash or paid out; in the example that cash is needed in spring 2027 to stay within the credit limit.

Separately, the cause lies in the contracts. TLN advises a joint reference point for the diesel price and, with rapid increases, weekly instead of monthly adjustment; in the example the monthly lag costs €34,500 and the lack of a clause on 40 percent of revenue €276,200. How a fixed price without an indexation clause works out in another sector, we calculated earlier in the article on a machine builder and the steel price.

When this story does not apply

A transport company with an ample cash position and no credit limit in sight only loses the interest on a provisional assessment that is too high, in the example €4,000 a year, and gets the money back in 2027. For such a company the provisional assessment is a forced savings account, and some directors we talk to like that. The same applies to a company that makes up the loss in the fourth quarter after all, for example because the diesel price falls and the toll is included in all rates from October; then the provisional assessment turns out to have been about right and taking action delivered nothing.

The story also does not apply to a company in a fiscal unity with a profitable sister company, because there the loss is offset within the year against the profit of the rest of the group and the parent company pays the assessment. And anyone who already made a loss in 2025 has no profit to carry back to: then only carry-forward remains, and stopping the instalments is the only cash flow you can still influence in 2026.

The do-it-yourself version

The proper method is a monthly results forecast for the rest of the year, with the diesel price and tolled kilometres per contract, from which your accountant calculates the expected tax every quarter and adjusts the provisional assessment.

The do-it-yourself version takes an hour. Take the result up to and including last month from your accounting software. Multiply the number of litres you still expect to fill up this year by the difference between the current bulk price and the price in your rates without a clause, and deduct that from the result. Add the tolled kilometres you will still drive times 20.1 cents minus the 22.3 percent discount, so times 15.6 cents, as costs, and add back the part your customers already pay as revenue. If the outcome is a loss, log in to Mijn Belastingdienst Zakelijk and set the provisional assessment to zero. If the outcome is a smaller profit than last year, multiply it by 19 percent and set the assessment to that amount. Put the date of your 2026 return in the diary before 1 June 2027, and tax interest is no longer an argument.

Questions for your adviser

We do not give tax advice; this article describes the scheme and shows what you need to seek advice on. Ask your accountant or tax adviser at least this: on what data is my provisional assessment for 2026 based, and what will be the basis for 2027; when will my 2025 assessment become final and can that be faster; what amount can I get back through provisional loss relief after the 2026 return, and when; what happens to the offset if I am in a fiscal unity or if the shareholders changed in 2026; and what obligations or risks does reducing the assessment to zero carry if the profit turns out positive after all.

Frequently asked questions about the provisional assessment in a loss year

Can I reduce my provisional corporate income tax assessment if I make a loss this year?

Yes. You can have the provisional assessment changed via Mijn Belastingdienst Zakelijk or your tax software, including to zero. The Dutch Tax Administration processes at most three increases a year and sets no maximum for reductions. In the worked example, a reduction in May 2026 stops seven instalments of €3,282, together €22,974.

How do I get last year's corporate income tax back if I make a loss this year?

A loss is first offset against the profit of the previous year. That happens with the assessment for the loss year, so after your tax return. After filing that return you can ask in writing for provisional loss relief, under which up to 80 percent of the loss is offset in advance, provided the assessment for the previous year is final. In the example that is €29,600 in spring 2027 and €6,500 with the final assessment.

What is the tax interest rate on corporate income tax in 2026?

Five percent from 1 January 2026, the same as for other taxes. For 2025 it is 6.5 percent and for 2024 7.5 percent, after the Supreme Court declared the higher rate for corporate income tax non-binding on 16 January 2026. You pay the interest from 1 July after the tax year, and not if you file the return before 1 June and the Dutch Tax Administration adopts it unchanged.

What does the HGV toll cost my transport company per year?

According to TLN, the average rate is 19.1 cents per kilometre at 2026 prices, with 20.1 cents for a Euro 6 tractor unit above 32 tonnes, and from 1 September to 31 December 2026 a discount of 22.3 percent applies. In the example, a fleet of 45 tractor units drives 3.2 million tolled kilometres a year; that is €646,700 a year without the discount, and €275,300 in the second half of 2026, minus €28,700 for the abolished Eurovignette. What you pay yourself depends on what you pass on; in the example 30 percent.

How do I calculate what the diesel price does to my profit?

Multiply your annual consumption in litres by the price increase per litre, and multiply that by the share of your revenue that has no diesel clause. In the example, 1,534,500 litres times €0.45 is €690,525, of which the 40 percent without a clause costs €276,200. Add the lag of the clause, in the example one twelfth of the part passed on. In this example, every cent per litre you do not pass on is €15,345 a year.

When do I get money back after a loss year?

The amount overpaid for the loss year itself comes back after your tax return, in the example in March 2027 if you file in February. The offset against the previous year's profit follows with the assessment for the loss year, with an advance of 80 percent on request after the return. The Dutch Tax Administration only pays interest on that money if, after 1 July of the following year, it takes more than eight weeks over a request or thirteen weeks over a return.

What is provisional loss relief?

A scheme under which, after your tax return for the loss year, the Dutch Tax Administration offsets up to 80 percent of the reported loss against the previous year's profit in advance, before the final assessment is issued. You apply in writing to your tax office, and the assessment for the previous year must be final. The remaining 20 percent follows with the final assessment for the loss year.

Further reading: Why a profitable SME still runs into cash flow problems, Rolling forecasts: steering in a moving market and What the ECB rate rise costs a technical wholesaler that lets its customers pay in 52 days.

← Back to knowledge base