Provisions and accruals at 31 December: a cost in the books that waits for an invoice or a payment in CIT

The Cost That Arrives Twice

I see this mistake every January. In December the office books an accrual for the client's electricity: 4 200 zł, estimated from the previous three bills. In mid-January the December invoice arrives in KSeF, someone books it as a December cost, and nobody reverses the accrual. The client's 2026 result now carries 8 400 zł of electricity for one month.

One line like that is a nuisance. Spread it across 25 full-books clients with a dozen accruals each, and it's the reason a year-end close that should take an afternoon of review takes three days of reconciling.

Provisions and accruals are the year-end item where the books and the tax return part ways most clearly. It's also where it's easiest to lose track of what went where. Like the write-downs of receivables I covered yesterday, it comes down to two lists, not one.

The Accounting Side: What Belongs in 2026

The Accounting Act asks for two related things at the balance sheet date.

Accruals (bierne rozliczenia międzyokresowe kosztów, art. 39(2)) cover probable liabilities that relate to the current year. Three typical groups:

• December services without an invoice by the closing date: energy, telecoms, transport, a subcontractor's last week of work, legal fees for a December matter.
• Future employee benefits: unused leave, retirement severance and jubilee awards, annual bonuses that are earned in 2026 but paid in 2027. Since an amendment, the Act says outright that these are accruals, and that they are shown in the balance sheet among provisions (art. 39(2a)). That is why people call it a "leave provision" even though technically it is an accrual.
• Costs for this year's close that are only billed later, most commonly the audit of the 2026 financial statements. Practice varies here; some policies accrue it in 2026, some book it in the year of the audit. Whatever the policy says, apply it the same way every year.

Provisions (rezerwy, art. 35d) cover liabilities that are certain or highly probable, where the amount can be reliably estimated but the timing or amount is not yet settled: a court case the client is likely to lose, warranty repairs, a loss on a contract already signed, a restructuring that has been decided and announced.

Both reduce the result for 2026. For an office, the practical difference is who supplies the number. The electricity accrual comes from the bank statements. The leave accrual comes from payroll. The litigation provision comes from the client's lawyer, and nobody at the office should invent it.

Before you start building the list, check the client's accounting policy. Smaller clients often use the simplifications the Act allows, including skipping some accruals and provisions or not recognising deferred tax. If the policy says so, the list gets shorter. If the policy says nothing, fix that before December, not in the middle of the close.

The Tax Side: Waiting for an Invoice or a Payment

The CIT Act treats this differently, and on purpose.

Provisions created under the Accounting Act are not a tax cost (art. 16(1)(27)). For indirect costs, the day a cost is incurred is the day it is booked on the basis of an invoice, or of another document if there is no invoice, except where the booking is a provision or an accrual (art. 15(4e)). The commentaries agree on the effect: the amount becomes deductible only once it is booked in some other way, typically on the basis of the invoice when it comes in.

In practice the tax column for each line reads one of these:

1. Invoice expected. The December electricity accrual is not a cost in 2026. When the invoice is booked, the cost is recognised under the normal rules. Which year an invoice issued on 2 January belongs to is a separate question, and I covered it in the post on year-end purchase invoices in KSeF.
2. Payment expected. Unused leave, retirement severance, jubilee awards: a cost when paid, not when accrued.
3. Salary rule. Salaries and bonuses are a cost in the month they are due for, if they are paid by the deadline (art. 15(4g)); if paid late, they are a cost when paid (art. 16(1)(57)). An annual bonus that the bonus rules make due for 2026 and pay by 31 March is commonly accepted as a 2026 cost. A discretionary bonus decided in February is usually a cost when paid. The authorities are not consistent here, so the office should read the client's bonus rules, not guess from the payslip name.
4. Provision. Litigation, warranty, onerous contracts: not a cost until the liability is actually settled and documented.

PIT has a parallel rule for full-books taxpayers, so the same two lists apply to partnerships of individuals.

Each line that goes into the books in 2026 but into tax in 2027 is a temporary difference. Clients that recognise deferred tax need it for the deferred tax asset. Clients that don't still need it, because in 2027 somebody has to remember to deduct the amount once the invoice or payment comes through.

The Size of the Job

Take an office with 25 full-books clients, the same illustrative office as yesterday. A realistic year-end picture:

Item	Lines across 25 clients
December services without an invoice	~150
Unused leave (per client, by employee)	~25 calculations, ~400 employees
Annual bonuses earned in 2026	~20
Audit fee, other close-related costs	~15
Provisions carried from 2025 (used, reversed, still needed)	~40
New provisions needing the client's or lawyer's input	~10

That is roughly 250 lines, of which perhaps 30 need real judgement. Done by hand, it is about two days of pulling statements, chasing payroll exports and copying last year's provisions into a new sheet. The other 220 lines are pattern work.

The mistakes repeat. The accrual for December electricity is not reversed when the invoice arrives, so the cost appears twice. The leave accrual is calculated from the 2025 leave balances because the 2026 export was never requested. A warranty provision from 2023 sits untouched for three years, because nobody checks whether the claims it covered ever came in. And the tax return takes the leave accrual as a 2026 cost, which an inspector will reverse.

What the Agent Prepares

An agent working on the client's ledger, bank statements, KSeF and the payroll export does the pattern work and leaves the judgement to the accountant:

• Finds missing December invoices. It lists suppliers who were paid monthly during 2026, from the bank statements, and whose December invoice is not in KSeF by the closing date. For each one it proposes an accrual based on the previous three months, with the range.
• Builds the employee lines from the payroll export: leave balances times the daily rate with social contributions, retirement and jubilee data for the actuary where the client uses one, and the bonus rules with their payment dates.
• Carries forward last year's provisions with a status for each: used (and against what), reversed, still needed, or no movement for 12 months (flagged for the accountant).
• Adds the tax column to every line: cost in 2026, waiting for an invoice, waiting for payment, or salary rule with the deadline that decides it. The result feeds the deferred tax calculation and the 2027 follow-up list.
• In January, matches incoming invoices to the accruals, proposes the reversal, and shows the difference between the estimate and the invoice, so the cost is booked once.

It doesn't estimate the litigation provision, doesn't set the actuarial assumptions, and doesn't decide whether the audit fee belongs in 2026. Those are signed decisions. Its job is to get the 220 routine lines reconciled first, so the accountant spends the review on the 30 that matter. It fits into the month-end close the office already runs, and the supplier list overlaps with the balance confirmations sent in December.

Ask Payroll Now

The most useful thing an office can do in October is ask each full-books client for two things: the leave balances as at 30 November and the current bonus rules with their payment dates. Both take the client ten minutes. Both decide numbers you would otherwise estimate under pressure in January.

If you'd like to see the two lists on one of your clients' data, write to me. I'll run the supplier check and the provision carry-forward on last year's closing and show you which lines went into the books and the tax return in different years.